diff --git a/crates/engine/src/commands/file.rs b/crates/engine/src/commands/file.rs
index fe32d28a..fd215751 100644
--- a/crates/engine/src/commands/file.rs
+++ b/crates/engine/src/commands/file.rs
@@ -4,7 +4,7 @@ use effectcraft_color::Label;
 use effectcraft_project::{FootageKind, ItemId, ItemKind, LayerSource, Project};
 use serde_json::{Value, json};
 
-use super::{CommandSpec, always, bad, str_p};
+use super::{CommandSpec, always, b_p, bad, str_p};
 use crate::{EngineError, Result, Session, cmd};
 
 fn has_path(s: &Session) -> std::result::Result<(), String> {
@@ -103,16 +103,70 @@ fn revert(s: &mut Session, _: &Value) -> Result<Value> {
 
 /// File ▸ Import; with `addToComp` (files dropped on the Timeline or the Composition viewer) they
 /// also become layers of the active comp ([`add_to_comp`]).
+///
+/// With `background` (files dropped on the window or picked in the Import dialog) the files are
+/// probed on a background thread, so decoding a slow video doesn't freeze the app: the job shows
+/// the file being read and how many are left (Window ▸ Progress, `jobs.list`), then adds them in
+/// one undo step, selects them and reports how many arrived ("Imported 3 items").
 fn import_cmd(s: &mut Session, p: &Value) -> Result<Value> {
     let target = s.active_comp_id();
-    let mut r = import(s, p)?;
-    let errors = add_to_comp(s, &r, target, p);
+    let mut pending = prepare_import(s, p)?;
+    if b_p(p, "background").unwrap_or(false) && !pending.paths.is_empty() {
+        let paths = std::mem::take(&mut pending.paths);
+        let total = paths.len();
+        let label = match paths.first() {
+            Some(one) if total == 1 => format!("Importing {}", file_name(one)),
+            _ => format!("Importing {total} files"),
+        };
+        let p = p.clone();
+        return s.spawn_task("import", label, false, move |ctl| {
+            let mut probed = Vec::with_capacity(total);
+            for (k, path) in paths.into_iter().enumerate() {
+                ctl.message(format!("{} ({} of {total})", file_name(&path), k + 1));
+                if !ctl.progress(k as u64, total as u64) {
+                    return Err(crate::render_queue::CANCELLED.into());
+                }
+                let r = pending.prober.probe(&path);
+                probed.push(r);
+            }
+            ctl.progress(total as u64, total as u64);
+            let apply: crate::jobs::Apply = Box::new(move |s: &mut Session| {
+                let made = pending.comps.len() + probed.iter().filter(|r| r.is_ok()).count();
+                let mut r = add_footage(s, pending, probed)?;
+                finish_import(s, &mut r, target, &p);
+                let mut toast = format!("Imported {made} item{}", if made == 1 { "" } else { "s" });
+                let errors: Vec<&str> = r["errors"].as_array().into_iter().flatten().filter_map(Value::as_str).collect();
+                match errors.as_slice() {
+                    [] => {}
+                    [one] => toast = format!("{toast}. {one}"),
+                    [first, rest @ ..] => toast = format!("{toast}. {first} (and {} more)", rest.len()),
+                }
+                r["toast"] = json!(toast);
+                Ok(r)
+            });
+            Ok(apply)
+        });
+    }
+    let probed = pending.paths.iter().map(|path| pending.prober.probe(path)).collect();
+    let mut r = add_footage(s, pending, probed)?;
+    finish_import(s, &mut r, target, p);
+    Ok(r)
+}
+
+/// The file name of a path, for labels.
+fn file_name(path: &str) -> String {
+    std::path::Path::new(path).file_name().map(|n| n.to_string_lossy().to_string()).unwrap_or_else(|| path.to_string())
+}
+
+/// After an import (its result `r`): with `addToComp`, the new items become layers of `target`;
+/// what couldn't be added joins the result's errors.
+fn finish_import(s: &mut Session, r: &mut Value, target: Option<ItemId>, p: &Value) {
+    let errors = add_to_comp(s, r, target, p);
     if !errors.is_empty()
         && let Some(e) = r.get_mut("errors").and_then(Value::as_array_mut)
     {
         e.extend(errors.into_iter().map(Value::from));
     }
-    Ok(r)
 }
 
 /// With `addToComp`, put what an import (its result `r`) made into `target`, the comp that was
@@ -149,7 +203,115 @@ pub(crate) fn add_to_comp(s: &mut Session, r: &Value, target: Option<ItemId>, p:
     errors
 }
 
+/// File ▸ Import, all in one go (scripts and commands built on it); see [`import_cmd`].
 pub(crate) fn import(s: &mut Session, p: &Value) -> Result<Value> {
+    let pending = prepare_import(s, p)?;
+    let probed = pending.paths.iter().map(|path| pending.prober.probe(path)).collect();
+    add_footage(s, pending, probed)
+}
+
+/// An import whose layered files are already compositions: the files left to probe as footage,
+/// how, and what the import made so far.
+struct PendingImport {
+    paths: Vec<String>,
+    prober: Prober,
+    comps: Vec<u64>,
+    items: Vec<u64>,
+    errors: Vec<String>,
+}
+
+/// Everything probing a file needs, apart from the session (it can run on a background thread).
+struct Prober {
+    importer: Option<std::sync::Arc<dyn crate::Importer>>,
+    services: std::sync::Arc<dyn crate::Services>,
+    /// Settings ▸ Import ▸ Report Missing Frames.
+    report_missing_frames: bool,
+    /// Settings ▸ Import ▸ Interpret Unlabeled Alpha As, for stills and for movies.
+    still_alpha: Option<effectcraft_project::AlphaMode>,
+    movie_alpha: Option<effectcraft_project::AlphaMode>,
+    /// Settings ▸ Import ▸ Sequence Footage frames per second.
+    sequence_rate: effectcraft_time::FrameRate,
+    /// PDF / Illustrator page (0-based).
+    page: u32,
+    /// Choose Layer: one layer of a Photoshop document.
+    psd_layer: Option<Value>,
+}
+
+/// A file probed as footage.
+struct Probed {
+    path: String,
+    footage: effectcraft_project::Footage,
+    /// Its alpha is unlabeled and Settings say Ask User: open Interpret Footage.
+    ask_alpha: bool,
+    warning: Option<String>,
+}
+
+impl Prober {
+    /// Probe `path` as footage; the error names the file.
+    fn probe(&self, path: &str) -> std::result::Result<Probed, String> {
+        let fail = |e: String| format!("{path}: {e}");
+        // Data files (JSON, CSV, TSV) for data-driven animation: kept as text in the project.
+        if let Some(f) = data_footage(self.services.as_ref(), path) {
+            return f.map(|footage| Probed { path: path.to_string(), footage, ask_alpha: false, warning: None }).map_err(fail);
+        }
+        let importer = self.importer.as_ref().ok_or_else(|| fail("media import is not available in this build".into()))?;
+        let mut f = importer.probe(path).map_err(fail)?;
+        let mut warning = None;
+        // Settings ▸ Import ▸ Report Missing Frames.
+        if f.kind == FootageKind::Sequence
+            && self.report_missing_frames
+            && let Some(gaps) = missing_frames(&f.sequence)
+        {
+            warning = Some(format!("{path}: {gaps}"));
+        }
+        // Settings ▸ Import ▸ Interpret Unlabeled Alpha As.
+        let mut ask_alpha = false;
+        if f.alpha != effectcraft_project::AlphaMode::Ignore && !alpha_is_labeled(path, &f.codec) {
+            let setting = if f.kind == FootageKind::Video { self.movie_alpha } else { self.still_alpha };
+            match setting {
+                Some(a) => f.alpha = a,
+                None => ask_alpha = true,
+            }
+        }
+        // Settings ▸ Import ▸ Sequence Footage frames per second.
+        if f.kind == FootageKind::Sequence {
+            let r = self.sequence_rate;
+            let frames = f.frame_rate.frame_at(f.duration);
+            f.frame_rate = r;
+            f.duration = r.tick_of(frames.max(1));
+        }
+        // Page: another page of a PDF / Illustrator file.
+        if self.page > 0 && matches!(f.codec.as_str(), "PDF" | "AI") {
+            let doc = self
+                .services
+                .read_file(path)
+                .map_err(|e| e.to_string())
+                .and_then(|b| effectcraft_pdf::parse_page(&b, self.page as usize).map_err(|e| e.to_string()))
+                .map_err(fail)?;
+            (f.width, f.height) = doc.pixel_size();
+            f.page = self.page;
+        }
+        // Choose Layer: one layer of a Photoshop document (document-sized).
+        if let Some(sel) = &self.psd_layer
+            && f.codec == "PSD"
+        {
+            let (index, name) = self
+                .services
+                .read_file(path)
+                .ok()
+                .and_then(|b| effectcraft_psd::Psd::parse(b).ok())
+                .and_then(|d| find_psd_layer(&d, sel))
+                .ok_or_else(|| fail(format!("no layer {sel}")))?;
+            f.layer = Some(effectcraft_project::SourceLayer { index: index as u32, name, layer_size: false, embedded: None, placed: false });
+        }
+        Ok(Probed { path: path.to_string(), footage: f, ask_alpha, warning })
+    }
+}
+
+/// The first part of an import: read the parameters, note the files as recent footage, and
+/// import layered files (Photoshop, PDF, Illustrator, EPS) as compositions when `importAs` (or,
+/// for dropped files, Default Drag Import As) asks for that. The other files are left to probe.
+fn prepare_import(s: &mut Session, p: &Value) -> Result<PendingImport> {
     let paths: Vec<String> = match p.get("paths").or(p.get("path")) {
         Some(Value::Array(a)) => a.iter().filter_map(|v| v.as_str().map(str::to_string)).collect(),
         Some(Value::String(x)) => vec![x.clone()],
@@ -178,8 +340,8 @@ pub(crate) fn import(s: &mut Session, p: &Value) -> Result<Value> {
         },
     };
     let mut paths = paths;
-    let mut out_comps = vec![];
-    let mut ids = vec![];
+    let mut comps = vec![];
+    let mut items = vec![];
     let mut errors = vec![];
     if let Some(retain) = retain {
         let mut rest = vec![];
@@ -189,9 +351,9 @@ pub(crate) fn import(s: &mut Session, p: &Value) -> Result<Value> {
                 Ok(b) if effectcraft_pdf::sniff(&b).is_some() && !path.to_ascii_lowercase().ends_with(".svg") => {
                     // PDF / Illustrator / EPS: one layer per file layer.
                     match import_vector_comp(s, &path, &b, page) {
-                        Ok((comp, items)) => {
-                            out_comps.push(comp);
-                            ids.extend(items);
+                        Ok((comp, made)) => {
+                            comps.push(comp);
+                            items.extend(made);
                         }
                         Err(e) => errors.push(e.to_string()),
                     }
@@ -203,127 +365,76 @@ pub(crate) fn import(s: &mut Session, p: &Value) -> Result<Value> {
                 }
             };
             match import_psd_comp(s, &path, bytes, retain) {
-                Ok((comp, items, warnings)) => {
-                    out_comps.push(comp);
-                    ids.extend(items);
+                Ok((comp, made, warnings)) => {
+                    comps.push(comp);
+                    items.extend(made);
                     errors.extend(warnings);
                 }
                 Err(e) => errors.push(format!("{path}: {e}")),
             }
         }
         paths = rest;
-        if paths.is_empty() {
-            if let Some(c) = out_comps.first() {
-                s.open_comp(effectcraft_project::ItemId(*c));
-            }
-            return Ok(json!({"items": ids, "comps": out_comps, "errors": errors}));
-        }
     }
-    let mut probed = vec![];
-    let psd_layer = p.get("layer").cloned();
-    let seq_rate = effectcraft_time::FrameRate::from_f64(s.prefs.import.sequence_fps);
-    let mut ask_alpha = vec![];
+    let prober = Prober {
+        importer: s.importer.clone(),
+        services: s.services.clone(),
+        report_missing_frames: s.prefs.import.report_missing_frames,
+        still_alpha: s.prefs.unlabeled_alpha(false),
+        movie_alpha: s.prefs.unlabeled_alpha(true),
+        sequence_rate: effectcraft_time::FrameRate::from_f64(s.prefs.import.sequence_fps),
+        page,
+        psd_layer: p.get("layer").cloned(),
+    };
+    Ok(PendingImport { paths, prober, comps, items, errors })
+}
+
+/// The last part of an import: add the probed files to the project (one undo step) and select
+/// everything the import made, so the Project panel shows it.
+fn add_footage(s: &mut Session, pending: PendingImport, probed: Vec<std::result::Result<Probed, String>>) -> Result<Value> {
+    let PendingImport { comps, mut items, mut errors, .. } = pending;
+    let mut found = vec![];
     let mut warnings = vec![];
-    for path in &paths {
-        // Data files (JSON, CSV, TSV) for data-driven animation: kept as text in the project.
-        if let Some(f) = data_footage(s, path) {
-            match f {
-                Ok(f) => probed.push((path.clone(), f)),
-                Err(e) => errors.push(format!("{path}: {e}")),
+    for r in probed {
+        match r {
+            Ok(f) => {
+                warnings.extend(f.warning.clone());
+                found.push(f);
             }
-            continue;
-        }
-        let Some(importer) = s.importer.clone() else {
-            errors.push(format!("{path}: media import is not available in this build"));
-            continue;
-        };
-        match importer.probe(path) {
-            Ok(mut f) => {
-                // Settings ▸ Import ▸ Report Missing Frames.
-                if f.kind == FootageKind::Sequence
-                    && s.prefs.import.report_missing_frames
-                    && let Some(gaps) = missing_frames(&f.sequence)
-                {
-                    warnings.push(format!("{path}: {gaps}"));
-                }
-                // Settings ▸ Import ▸ Interpret Unlabeled Alpha As.
-                if f.alpha != effectcraft_project::AlphaMode::Ignore && !alpha_is_labeled(path, &f.codec) {
-                    match s.prefs.unlabeled_alpha(f.kind == FootageKind::Video) {
-                        Some(a) => f.alpha = a,
-                        None => ask_alpha.push(paths.iter().position(|x| x == path).unwrap_or(0)),
-                    }
-                }
-                // Settings ▸ Import ▸ Sequence Footage frames per second.
-                if f.kind == FootageKind::Sequence {
-                    let r = seq_rate;
-                    let frames = f.frame_rate.frame_at(f.duration);
-                    f.frame_rate = r;
-                    f.duration = r.tick_of(frames.max(1));
-                }
-                // Page: another page of a PDF / Illustrator file.
-                if page > 0 && matches!(f.codec.as_str(), "PDF" | "AI") {
-                    match s
-                        .services
-                        .read_file(path)
-                        .map_err(|e| e.to_string())
-                        .and_then(|b| effectcraft_pdf::parse_page(&b, page as usize).map_err(|e| e.to_string()))
-                    {
-                        Ok(doc) => {
-                            (f.width, f.height) = doc.pixel_size();
-                            f.page = page;
-                        }
-                        Err(e) => {
-                            errors.push(format!("{path}: {e}"));
-                            continue;
-                        }
-                    }
-                }
-                // Choose Layer: one layer of a Photoshop document (document-sized).
-                if let Some(sel) = &psd_layer
-                    && f.codec == "PSD"
-                {
-                    match s.services.read_file(path).ok().and_then(|b| effectcraft_psd::Psd::parse(b).ok()).and_then(|d| find_psd_layer(&d, sel)) {
-                        Some((index, name)) => {
-                            f.layer = Some(effectcraft_project::SourceLayer { index: index as u32, name, layer_size: false, embedded: None, placed: false })
-                        }
-                        None => {
-                            errors.push(format!("{path}: no layer {sel}"));
-                            continue;
-                        }
-                    }
-                }
-                probed.push((path.clone(), f))
-            }
-            Err(e) => errors.push(format!("{path}: {e}")),
+            Err(e) => errors.push(e),
         }
     }
     let mut asked: Vec<u64> = vec![];
-    s.edit("Import", None, |proj, st| {
-        for (path, f) in probed {
-            let name = std::path::Path::new(&path).file_name().map(|n| n.to_string_lossy().to_string()).unwrap_or(path.clone());
-            let name = match &f.layer {
-                Some(l) => format!("{}/{name}", l.name),
-                None if f.page > 0 => format!("{name} (Page {})", f.page + 1),
-                None => name,
-            };
-            let label = match f.kind {
-                FootageKind::Still | FootageKind::Sequence => Label::Lavender,
-                FootageKind::Audio => Label::SeaFoam,
-                FootageKind::Video | FootageKind::Model => Label::Aqua,
-                FootageKind::Data => Label::Sandstone,
-            };
-            let ask = ask_alpha.contains(&paths.iter().position(|x| *x == path).unwrap_or(usize::MAX));
-            let id = proj.add_item(&name, label, None, ItemKind::Footage(f));
-            ids.push(id.0);
-            if ask {
-                asked.push(id.0);
+    let made: Vec<ItemId> = comps.iter().map(|c| ItemId(*c)).collect();
+    if !found.is_empty() {
+        s.edit("Import", None, |proj, st| {
+            let mut selection = made;
+            for f in found {
+                let name = file_name(&f.path);
+                let footage = f.footage;
+                let name = match &footage.layer {
+                    Some(l) => format!("{}/{name}", l.name),
+                    None if footage.page > 0 => format!("{name} (Page {})", footage.page + 1),
+                    None => name,
+                };
+                let label = match footage.kind {
+                    FootageKind::Still | FootageKind::Sequence => Label::Lavender,
+                    FootageKind::Audio => Label::SeaFoam,
+                    FootageKind::Video | FootageKind::Model => Label::Aqua,
+                    FootageKind::Data => Label::Sandstone,
+                };
+                let id = proj.add_item(&name, label, None, ItemKind::Footage(footage));
+                items.push(id.0);
+                if f.ask_alpha {
+                    asked.push(id.0);
+                }
+                selection.push(id);
             }
-            st.project_selection = vec![id];
-        }
-        Ok(())
-    })?;
-    if let Some(c) = out_comps.first() {
-        s.open_comp(effectcraft_project::ItemId(*c));
+            st.project_selection = selection;
+            Ok(())
+        })?;
+    }
+    if let Some(c) = comps.first() {
+        s.open_comp(ItemId(*c));
     }
     for w in &warnings {
         s.events.push(crate::Event::Toast { message: w.clone(), error: true });
@@ -332,7 +443,7 @@ pub(crate) fn import(s: &mut Session, p: &Value) -> Result<Value> {
     if let Some(first) = asked.first() {
         s.events.push(crate::Event::Frontend { command: "file.interpretFootage".into(), params: json!({"item": first, "reason": "unlabeledAlpha"}) });
     }
-    Ok(json!({"items": ids, "comps": out_comps, "errors": errors, "warnings": warnings, "unlabeledAlpha": asked}))
+    Ok(json!({"items": items, "comps": comps, "errors": errors, "warnings": warnings, "unlabeledAlpha": asked}))
 }
 
 /// Whether a file format states how its alpha is stored (PNG, GIF, WebP and PSD are straight by
@@ -416,13 +527,13 @@ fn import_vector_comp(s: &mut Session, path: &str, bytes: &[u8], page: u32) -> R
 pub const DATA_EXTENSIONS: &[&str] = &["json", "csv", "tsv"];
 
 /// A data footage item for `path` (JSON / CSV / TSV), `None` for other files.
-pub(crate) fn data_footage(s: &Session, path: &str) -> Option<std::result::Result<effectcraft_project::Footage, String>> {
+pub(crate) fn data_footage(services: &dyn crate::Services, path: &str) -> Option<std::result::Result<effectcraft_project::Footage, String>> {
     let ext = std::path::Path::new(path).extension().and_then(|e| e.to_str()).unwrap_or("").to_ascii_lowercase();
     if !DATA_EXTENSIONS.contains(&ext.as_str()) {
         return None;
     }
     Some((|| {
-        let bytes = s.services.read_file(path).map_err(|e| e.to_string())?;
+        let bytes = services.read_file(path).map_err(|e| e.to_string())?;
         let text = String::from_utf8(bytes).map_err(|_| "data files must be UTF-8 text".to_string())?;
         if ext == "json" {
             serde_json::from_str::<Value>(text.trim_start_matches('\u{feff}')).map_err(|e| format!("invalid JSON: {e}"))?;
@@ -585,7 +696,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "File...",
             ["File", "Import"],
             Some("Cmd+I"),
-            "{paths: [string], importAs?: footage|composition|compositionLayerSizes (Photoshop, PDF, Illustrator and EPS files), layer?: name|index (footage of one Photoshop layer), page?: number from 1 (PDF / Illustrator page), drag?: bool (dropped files: Settings ▸ Import ▸ Default Drag Import As), addToComp?: bool (also add them to the active comp, at time?, index?, position? as in layer.addItem)}",
+            "{paths: [string], importAs?: footage|composition|compositionLayerSizes (Photoshop, PDF, Illustrator and EPS files), layer?: name|index (footage of one Photoshop layer), page?: number from 1 (PDF / Illustrator page), drag?: bool (dropped files: Settings ▸ Import ▸ Default Drag Import As), addToComp?: bool (also add them to the active comp, at time?, index?, position? as in layer.addItem), background?: bool (probe the files in a background job, jobs.list / jobs.wait; returns {job})}",
             always,
             import_cmd
         ),
diff --git a/crates/engine/src/jobs.rs b/crates/engine/src/jobs.rs
index f022a312..229d1950 100644
--- a/crates/engine/src/jobs.rs
+++ b/crates/engine/src/jobs.rs
@@ -1,6 +1,7 @@
 //! Background jobs: one list (Window ▸ Progress, `jobs.list`, `jobs.cancel`) over the render
 //! queue, the analyses (tracker, mask tracker, Warp Stabilizer, 3D Camera Tracker, Roto Brush) and
-//! the generic background tasks started here (Content-Aware Fill, Scene Edit Detection).
+//! the generic background tasks started here (Content-Aware Fill, Scene Edit Detection, footage
+//! checks and imports).
 //!
 //! A generic task runs a closure on a background thread (inline on wasm32 or when the caller
 //! waits). The closure reports progress through [`TaskCtl`] and returns an [`Apply`]: a function
@@ -162,7 +163,8 @@ impl Session {
         let cancelled = t.ctl.cancelled();
         let (status, message, result) = match r {
             Some(Ok(apply)) if !cancelled => match apply(self) {
-                Ok(v) => ("done", String::new(), v),
+                // A task may say how it went (`toast`: "Imported 3 items").
+                Ok(v) => ("done", v.get("toast").and_then(Value::as_str).unwrap_or_default().to_string(), v),
                 Err(e) => ("failed", e.to_string(), Value::Null),
             },
             Some(Ok(_)) => ("cancelled", String::new(), Value::Null),
@@ -180,6 +182,7 @@ impl Session {
             seconds: t.started.elapsed().as_secs_f64(),
         };
         let toast = match status {
+            "done" if !message.is_empty() => message.clone(),
             "done" => format!("{} finished", t.label),
             "cancelled" => format!("{} cancelled", t.label),
             _ => format!("{} failed: {message}", t.label),
diff --git a/crates/engine/src/tests.rs b/crates/engine/src/tests.rs
index ef467b93..0fa0fd0f 100644
--- a/crates/engine/src/tests.rs
+++ b/crates/engine/src/tests.rs
@@ -96,6 +96,69 @@ fn imported_files_go_into_the_comp_where_they_were_dropped() {
     assert!(s.execute("layer.addItem", json!({"item": "a.png", "position": [1.0]})).is_err(), "position needs x and y");
 }
 
+/// #270: files dropped or picked in the Import dialog (`file.import {background}`) are probed in
+/// a background job that says which file it is reading and how many are left; then they arrive
+/// in one undo step, all selected, with a count. The same file imported again arrives again.
+#[test]
+fn background_imports_report_progress_and_select_what_arrived() {
+    use effectcraft_project::{Footage, FootageKind, ItemId};
+    use std::sync::Arc;
+    use std::sync::atomic::{AtomicUsize, Ordering};
+    /// Probes file k once `allow` > k (a slow video; 5 s at most, so an import that waits for it
+    /// fails the test instead of hanging it); `.xyz` files fail.
+    struct Gated {
+        started: AtomicUsize,
+        allow: Arc<AtomicUsize>,
+    }
+    impl crate::Importer for Gated {
+        fn probe(&self, path: &str) -> Result<Footage, String> {
+            let k = self.started.fetch_add(1, Ordering::SeqCst);
+            let until = std::time::Instant::now() + std::time::Duration::from_secs(5);
+            while self.allow.load(Ordering::SeqCst) <= k && std::time::Instant::now() < until {
+                std::thread::sleep(std::time::Duration::from_millis(1));
+            }
+            if path.ends_with(".xyz") {
+                return Err("unsupported file".into());
+            }
+            Ok(Footage { path: path.into(), kind: FootageKind::Still, width: 64, height: 32, has_video: true, ..Default::default() })
+        }
+    }
+    let allow = Arc::new(AtomicUsize::new(1));
+    let mut s = Session { importer: Some(Arc::new(Gated { started: AtomicUsize::new(0), allow: allow.clone() })), ..Default::default() };
+    s.execute("comp.new", json!({"name": "Main", "width": 320, "height": 180, "frameRate": 30, "duration": 4})).unwrap();
+    let undo = s.history.undo.len();
+    let r = s.execute("file.import", json!({"paths": ["/drop/a.png", "/drop/b.png", "/drop/a.png"], "background": true})).unwrap();
+    let job = r["job"].as_str().unwrap().to_string();
+    // The first file is through; the second is being read.
+    let running = |s: &mut Session| s.execute("jobs.list", json!({})).unwrap()["running"].as_array().unwrap().clone();
+    let deadline = std::time::Instant::now() + std::time::Duration::from_secs(10);
+    while running(&mut s)[0]["done"] != json!(1) && std::time::Instant::now() < deadline {
+        std::thread::sleep(std::time::Duration::from_millis(2));
+    }
+    let row = running(&mut s)[0].clone();
+    assert_eq!(row["id"], json!(job));
+    assert_eq!(row["label"], json!("Importing 3 files"));
+    assert_eq!(row["message"], json!("b.png (2 of 3)"));
+    assert_eq!((row["done"].as_u64(), row["total"].as_u64()), (Some(1), Some(3)));
+    assert!(s.project.items.values().all(|i| i.name != "a.png"), "nothing is added before the import finishes");
+    allow.store(usize::MAX, Ordering::SeqCst);
+    s.execute("jobs.wait", json!({})).unwrap();
+    let names = |s: &Session, ids: &[ItemId]| ids.iter().map(|i| s.project.item(*i).unwrap().name.clone()).collect::<Vec<_>>();
+    assert_eq!(names(&s, &s.state.project_selection), ["a.png", "b.png", "a.png"], "everything imported is selected, the same file twice too");
+    assert_eq!(s.history.undo.len(), undo + 1, "one undo step");
+    let rec = s.job_log.last().unwrap();
+    assert_eq!((rec.status.as_str(), rec.message.as_str()), ("done", "Imported 3 items"));
+    assert!(s.drain_events().iter().any(|e| matches!(e, crate::Event::Toast { message, .. } if message == "Imported 3 items")));
+    // Dropped on the viewer: they become layers too; a file that can't be read is reported.
+    s.execute("file.import", json!({"paths": ["/drop/c.png", "/drop/d.xyz"], "background": true, "addToComp": true, "position": [10.0, 20.0]})).unwrap();
+    s.execute("jobs.wait", json!({})).unwrap();
+    assert_eq!(s.active_comp().unwrap().layers.iter().map(|l| l.name.as_str()).collect::<Vec<_>>(), ["c.png"]);
+    assert_eq!(s.job_log.last().unwrap().message, "Imported 1 item. /drop/d.xyz: unsupported file");
+    // Agents and scripts import at once by default.
+    let r = s.execute("file.import", json!({"paths": ["/drop/e.png"]})).unwrap();
+    assert_eq!(r["items"].as_array().map(Vec::len), Some(1));
+}
+
 /// Audio, Lock and Shy don't change pixels: toggling them keeps the cached layers (#103).
 #[test]
 fn audio_lock_and_shy_keep_cached_layers() {
diff --git a/crates/ui-egui/src/lib.rs b/crates/ui-egui/src/lib.rs
index d35630b8..691a3385 100644
--- a/crates/ui-egui/src/lib.rs
+++ b/crates/ui-egui/src/lib.rs
@@ -1383,7 +1383,7 @@ impl EffectcraftApp {
             self.session.poll_mask_track();
             ctx.request_repaint_after(std::time::Duration::from_millis(50));
         }
-        // Background tasks (Content-Aware Fill, Scene Edit Detection).
+        // Background tasks (Content-Aware Fill, Scene Edit Detection, imports).
         if !self.session.tasks.is_empty() {
             self.session.poll_jobs();
             ctx.request_repaint_after(std::time::Duration::from_millis(100));
@@ -1451,10 +1451,13 @@ impl EffectcraftApp {
         panels::scriptui_view::sync_panels(self);
         panels::scriptui_view::show_windows(self, &ctx);
         panels::learn::coach(self, &ctx);
-        self.draw_toast(ui, full);
+        let lift = panels::media_panels::import_card(self, ui, full);
+        self.draw_toast(ui, full, lift);
     }
 
-    fn draw_toast(&mut self, ui: &mut egui::Ui, full: egui::Rect) {
+    /// The status message or the latest toast, bottom left (`lift` points higher while the
+    /// Importing card is there).
+    fn draw_toast(&mut self, ui: &mut egui::Ui, full: egui::Rect, lift: f32) {
         let now = ui.input(|i| i.time);
         let msg = if !self.ui.status.is_empty() {
             Some(self.ui.status.clone())
@@ -1463,11 +1466,12 @@ impl EffectcraftApp {
         };
         if let Some(m) = msg {
             let t = &self.tokens;
-            let galley = ui.painter().layout_no_wrap(m, Tokens::ui(12.0), t.text);
-            let r = egui::Rect::from_min_size(egui::pos2(full.min.x + 16.0, full.max.y - 44.0), galley.size() + egui::vec2(24.0, 14.0));
+            let galley = ui.painter().layout_no_wrap(m.clone(), Tokens::ui(12.0), t.text);
+            let r = egui::Rect::from_min_size(egui::pos2(full.min.x + 16.0, full.max.y - 44.0 - lift), galley.size() + egui::vec2(24.0, 14.0));
             ui.painter().rect_filled(r, 6.0, t.panel_bg);
             ui.painter().rect_stroke(r, 6.0, egui::Stroke::new(1.0, t.field_border), egui::StrokeKind::Inside);
             ui.painter().galley(r.min + egui::vec2(12.0, 7.0), galley, t.text);
+            self.auto.add("toast", r, &m);
             let resp = ui.interact(r, egui::Id::new("toast"), egui::Sense::click());
             if resp.clicked() {
                 self.ui.status.clear();
diff --git a/crates/ui-egui/src/menus.rs b/crates/ui-egui/src/menus.rs
index 1cef8b57..388658aa 100644
--- a/crates/ui-egui/src/menus.rs
+++ b/crates/ui-egui/src/menus.rs
@@ -173,7 +173,8 @@ pub fn reveal(app: &mut EffectcraftApp, kind: &str, now: f64, add: bool) {
     } else {
         kinds = vec![kind.to_string()];
     }
-    tl.apply_reveal(&targets, kinds);
+    tl.apply_reveal(&targets, kinds.clone());
+    crate::panels::timeline::open_revealed(app, &targets, &kinds);
 }
 
 /// Show Time Remap on the layers of a `layer.enableTimeRemap` (`layers` by id, else the
@@ -1073,6 +1074,10 @@ pub fn frontend(app: &mut EffectcraftApp, ctx: &egui::Context, id: &str, p: Valu
             if !shown.is_empty() {
                 tl.apply_reveal(&shown, vec!["props".into()]);
             }
+            // Properties inside effects (puppet pins…) show under their effect, twirled open.
+            for (layer, prop) in props.iter().filter_map(|x| Some((x.get("layer")?.as_u64()?, x.get("prop")?.as_u64()?))) {
+                crate::panels::timeline::open_effect_paths(app, layer, &[prop]);
+            }
             json!({"revealed": found.len()})
         }
         _ => return Err(format!("`{id}` is not a frontend command")),
@@ -1153,6 +1158,10 @@ fn file_dialog(app: &mut EffectcraftApp, id: &str, params: &Value) -> Option<Res
     };
     let Some(v) = picked else { return Some(Ok(Value::Null)) };
     p.insert(key.to_string(), v);
+    // Picked files import in the background, with the Importing card showing progress (#270).
+    if matches!(id, "file.import" | "file.importMultiple") {
+        p.insert("background".into(), Value::Bool(true));
+    }
     // Photoshop files ask how to import them first.
     if id == "file.import" && crate::panels::dialogs::open_form(app, id, &Value::Object(p.clone())) {
         return Some(Ok(json!({"dialog": id})));
diff --git a/crates/ui-egui/src/panels/media_panels.rs b/crates/ui-egui/src/panels/media_panels.rs
index f961b9de..ec903027 100644
--- a/crates/ui-egui/src/panels/media_panels.rs
+++ b/crates/ui-egui/src/panels/media_panels.rs
@@ -342,9 +342,7 @@ pub fn progress(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         let frac = j.fraction.unwrap_or(0.0) as f32;
         let pct = j.fraction.map(|f| format!("{:.0} %", f * 100.0)).unwrap_or_else(|| "…".into());
         p.text(pos2(x0 + w - 70.0, y + 8.0), Align2::RIGHT_CENTER, format!("{pct}  {}", j.message), Tokens::ui(11.0), t.text_dim);
-        let bar = Rect::from_min_size(pos2(x0, y + 20.0), vec2(w - 76.0, 6.0));
-        p.rect_filled(bar, 3.0, t.field_bg);
-        p.rect_filled(Rect::from_min_size(bar.min, vec2(bar.width() * frac.clamp(0.0, 1.0), bar.height())), 3.0, t.accent);
+        progress_bar(&p, Rect::from_min_size(pos2(x0, y + 20.0), vec2(w - 76.0, 6.0)), frac, &t);
         app.auto.add(&format!("progress.job.{}", j.id), Rect::from_min_size(pos2(x0, y), vec2(w, 28.0)), &j.label);
         if j.cancellable
             && kit::button(app, ui, Rect::from_min_size(pos2(x0 + w - 64.0, y + 12.0), vec2(64.0, 18.0)), &format!("progress.cancel.{}", j.id), "Cancel", false)
@@ -374,3 +372,39 @@ pub fn progress(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         }
     }
 }
+
+/// A job's progress bar (`frac` 0…1).
+fn progress_bar(p: &egui::Painter, bar: Rect, frac: f32, t: &Tokens) {
+    p.rect_filled(bar, 3.0, t.field_bg);
+    p.rect_filled(Rect::from_min_size(bar.min, vec2(bar.width() * frac.clamp(0.0, 1.0), bar.height())), 3.0, t.accent);
+}
+
+/// The Importing card, bottom left over the panels while files import in the background (dropped
+/// or picked in the Import dialog): the file being read, how many are left, and Cancel (#270).
+/// Returns the height it takes, so toasts sit above it.
+pub fn import_card(app: &mut EffectcraftApp, ui: &mut egui::Ui, full: Rect) -> f32 {
+    if app.session.tasks.is_empty() {
+        return 0.0;
+    }
+    let t = app.tokens;
+    let w = 320.0_f32.min(full.width() - 32.0).max(120.0);
+    let mut bottom = full.max.y - 16.0;
+    for j in app.session.jobs().into_iter().filter(|j| j.kind == "import" && j.running) {
+        let r = Rect::from_min_max(pos2(full.min.x + 16.0, bottom - 56.0), pos2(full.min.x + 16.0 + w, bottom));
+        let p = ui.painter();
+        p.rect_filled(r, 6.0, t.panel_bg);
+        p.rect_stroke(r, 6.0, Stroke::new(1.0, t.field_border), egui::StrokeKind::Inside);
+        let x0 = r.min.x + 12.0;
+        let inner = w - 24.0;
+        widgets::text_fit(p, pos2(x0, r.min.y + 15.0), Align2::LEFT_CENTER, &j.label, Tokens::medium(12.0), inner - 64.0, t.text);
+        widgets::text_fit(p, pos2(x0, r.min.y + 32.0), Align2::LEFT_CENTER, &j.message, Tokens::ui(11.5), inner, t.text_dim);
+        progress_bar(p, Rect::from_min_size(pos2(x0, r.min.y + 42.0), vec2(inner, 6.0)), j.fraction.unwrap_or(0.0) as f32, &t);
+        app.auto.add(&format!("import.job.{}", j.id), r, &j.message);
+        if kit::button(app, ui, Rect::from_min_size(pos2(r.max.x - 68.0, r.min.y + 6.0), vec2(56.0, 18.0)), &format!("import.cancel.{}", j.id), "Cancel", false)
+        {
+            kit::exec(app, "jobs.cancel", json!({"job": j.id}));
+        }
+        bottom = r.min.y - 8.0;
+    }
+    full.max.y - 16.0 - bottom
+}
diff --git a/crates/ui-egui/src/panels/puppet_tool.rs b/crates/ui-egui/src/panels/puppet_tool.rs
index 9fa8ac6a..4b0b8e9a 100644
--- a/crates/ui-egui/src/panels/puppet_tool.rs
+++ b/crates/ui-egui/src/panels/puppet_tool.rs
@@ -82,6 +82,16 @@ pub fn overlay(app: &EffectcraftApp, ctx: &egui::Context, cid: ItemId, layer: &L
     Some(overlay)
 }
 
+/// Keep a pin's keyframed Position in view in the Timeline after placing, moving or recording the
+/// pin in the viewer (#273).
+pub fn reveal_pin(app: &mut EffectcraftApp, layer: LayerId, pin: u64) {
+    let comp = app.session.active_comp();
+    let pos = comp.and_then(|c| c.layer(layer)?.props.find_group(pin)?.get("position")).filter(|p| p.is_animated()).map(|p| p.uid);
+    if let Some(pos) = pos {
+        super::timeline::keep_in_view(app, layer, pos);
+    }
+}
+
 /// Where a pin sits now (layer space): its Position, or (Bend / Starch / Overlap pins) its rest
 /// point carried along by the deformation.
 pub fn pin_position(mesh: &Mesh, def: &[[f64; 2]], p: &Pin) -> [f64; 2] {
diff --git a/crates/ui-egui/src/panels/timeline.rs b/crates/ui-egui/src/panels/timeline.rs
index 26ec3435..8bdacc0a 100644
--- a/crates/ui-egui/src/panels/timeline.rs
+++ b/crates/ui-egui/src/panels/timeline.rs
@@ -685,8 +685,11 @@ fn build_rows(app: &EffectcraftApp, comp: &Comp) -> Vec<Row> {
 fn reveal_rows(app: &EffectcraftApp, l: &Layer, kinds: &[String], rows: &mut Vec<Row>) {
     let tl = &app.ui.timeline;
     let has = |k: &str| kinds.iter().any(|r| r == k);
-    let group_rows = |rows: &mut Vec<Row>, g: &PropGroup, fx: bool| {
+    // Groups shown with their whole contents: the revealed properties inside aren't listed again.
+    let mut shown_groups: Vec<u64> = vec![];
+    let mut group_rows = |rows: &mut Vec<Row>, g: &PropGroup, fx: bool| {
         for g in g.groups() {
+            shown_groups.push(g.uid);
             rows.push(Row {
                 layer: l.id,
                 depth: 1,
@@ -751,11 +754,6 @@ fn reveal_rows(app: &EffectcraftApp, l: &Layer, kinds: &[String], rows: &mut Vec
             wanted.extend(found);
         }
     }
-    if !wanted.is_empty() {
-        let mut found = vec![];
-        collect_props(&l.props, &mut found, &|p| wanted.contains(&p.uid));
-        rows.extend(found.into_iter().map(|uid| Row { layer: l.id, depth: 1, kind: RowKind::Prop { uid } }));
-    }
     // SS: the selected properties and groups (as Animation ▸ Reveal Properties shows them).
     let selected: std::collections::BTreeSet<u64> = app.session.state.selected_props.iter().filter(|(lid, _)| *lid == l.id).map(|(_, u)| *u).collect();
     if has("props") || has("selected") {
@@ -784,17 +782,124 @@ fn reveal_rows(app: &EffectcraftApp, l: &Layer, kinds: &[String], rows: &mut Vec
             if open {
                 push_group(rows, l, g, 2, &tl.open_groups);
             }
+            shown_groups.push(g.uid);
         }
-        let mut found = vec![];
-        collect_props(&l.props, &mut found, &|p| prop_visible(p, l) && reveal_props.contains(&p.uid) && !wanted.contains(&p.uid));
-        rows.extend(found.into_iter().map(|uid| Row { layer: l.id, depth: 1, kind: RowKind::Prop { uid } }));
+        wanted.extend(picked.iter().copied());
     }
+    revealed_rows(rows, l, &wanted, &shown_groups, &tl.open_groups);
     if has("waveform")
         && let Some(item) = super::waveform::audio_item(&app.session.project, l)
     {
         rows.push(Row { layer: l.id, depth: 1, kind: RowKind::Waveform { item: item.0 } });
     }
 }
+
+/// Rows for the revealed properties `shown` of `l`, in tree order. Those inside an effect show
+/// under the effect and its groups, as in After Effects (Puppet ▸ Mesh 1 ▸ Deform ▸ Puppet
+/// Pin 1 ▸ Position: every pin's Position is told apart, #273); the others (Transform, masks…)
+/// on their own. Groups in `skip` already show with their contents.
+fn revealed_rows(rows: &mut Vec<Row>, l: &Layer, shown: &std::collections::BTreeSet<u64>, skip: &[u64], open: &std::collections::BTreeSet<u64>) {
+    struct Tree<'a> {
+        l: &'a Layer,
+        wanted: &'a dyn Fn(&Property) -> bool,
+        skip: &'a [u64],
+        open: &'a std::collections::BTreeSet<u64>,
+    }
+    fn holds(g: &PropGroup, wanted: &dyn Fn(&Property) -> bool) -> bool {
+        g.children.iter().any(|c| match c {
+            Node::Prop(p) => wanted(p),
+            Node::Group(sg) => holds(sg, wanted),
+        })
+    }
+    // A group holding revealed properties (twirled as the user left it), then those inside.
+    fn group(rows: &mut Vec<Row>, t: &Tree<'_>, g: &PropGroup, depth: usize) {
+        if t.skip.contains(&g.uid) || !holds(g, t.wanted) {
+            return;
+        }
+        let o = t.open.contains(&g.uid);
+        let fx = matches!(g.kind, GroupKind::Effect { .. }).then_some(g.enabled);
+        rows.push(Row { layer: t.l.id, depth, kind: RowKind::Group { uid: g.uid, name: g.name.clone(), open: o, has_children: true, fx, eye: None } });
+        if !o {
+            return;
+        }
+        for c in &g.children {
+            match c {
+                Node::Prop(p) if (t.wanted)(p) => rows.push(Row { layer: t.l.id, depth: depth + 1, kind: RowKind::Prop { uid: p.uid } }),
+                Node::Group(sg) => group(rows, t, sg, depth + 1),
+                Node::Prop(_) => {}
+            }
+        }
+    }
+    let wanted = |p: &Property| shown.contains(&p.uid) && prop_visible(p, l);
+    let tree = Tree { l, wanted: &wanted, skip, open };
+    for c in &l.props.children {
+        match c {
+            Node::Group(fx) if fx.match_id == "effects" => {
+                for e in fx.groups() {
+                    group(rows, &tree, e, 1);
+                }
+            }
+            Node::Group(g) => {
+                let mut found = vec![];
+                collect_props(g, &mut found, &wanted);
+                rows.extend(found.into_iter().map(|uid| Row { layer: l.id, depth: 1, kind: RowKind::Prop { uid } }));
+            }
+            Node::Prop(p) if wanted(p) => rows.push(Row { layer: l.id, depth: 1, kind: RowKind::Prop { uid: p.uid } }),
+            Node::Prop(_) => {}
+        }
+    }
+}
+
+/// Uids of the groups that hold property `uid` of `l`, outermost first.
+fn enclosing_groups(l: &Layer, uid: u64) -> Vec<u64> {
+    let path = l.props.path_of(uid).unwrap_or_default();
+    let mut ids: Vec<u64> = path.split('/').filter_map(|s| s.strip_prefix('@')?.parse().ok()).collect();
+    ids.pop();
+    ids
+}
+
+/// Twirl open the groups holding `props` of `layer` that sit inside effects, so their rows show
+/// (a U reveal, an EE reveal, a puppet pin placed or moved in the viewer).
+pub(crate) fn open_effect_paths(app: &mut EffectcraftApp, layer: u64, props: &[u64]) {
+    let Some(l) = app.session.active_comp().and_then(|c| c.layer(LayerId(layer))) else { return };
+    let Some(fx) = l.effects().map(|g| g.uid) else { return };
+    let mut open = vec![];
+    for p in props {
+        let path = enclosing_groups(l, *p);
+        if path.first() == Some(&fx) {
+            open.extend(path);
+        }
+    }
+    app.ui.timeline.open_groups.extend(open);
+}
+
+/// After a reveal shortcut that picks properties by state (EE expressions): those inside effects
+/// on `layers` show under their effect, twirled open.
+pub(crate) fn open_revealed(app: &mut EffectcraftApp, layers: &[u64], kinds: &[String]) {
+    for kind in kinds.iter().filter(|k| matches!(k.as_str(), "animated" | "expressions")) {
+        for id in layers {
+            let Some(l) = app.session.active_comp().and_then(|c| c.layer(LayerId(*id))) else { continue };
+            let mut found = vec![];
+            collect_props(&l.props, &mut found, &|p| prop_visible(p, l) && reveal_matches(p, &[], kind));
+            open_effect_paths(app, *id, &found);
+        }
+    }
+}
+
+/// After the viewer edits a property (a puppet pin placed, moved or recorded): when `layer` is
+/// twirled open, its groups open, and a U reveal of the layer takes it in, so its keyframes show
+/// (#273). A collapsed layer stays collapsed, as in After Effects.
+pub fn keep_in_view(app: &mut EffectcraftApp, layer: LayerId, prop: u64) {
+    if !app.ui.timeline.open_layers.contains(&layer.0) {
+        return;
+    }
+    open_effect_paths(app, layer.0, &[prop]);
+    let tl = &mut app.ui.timeline;
+    if tl.layer_reveal.get(&layer.0).is_some_and(|k| k.iter().any(|k| k == "props")) {
+        tl.reveal_props.insert(prop);
+    }
+}
+
 fn collect_props(g: &PropGroup, out: &mut Vec<u64>, f: &dyn Fn(&Property) -> bool) {
     for c in &g.children {
         match c {
diff --git a/crates/ui-egui/src/panels/viewer.rs b/crates/ui-egui/src/panels/viewer.rs
index 4d75b8b1..b2107570 100644
--- a/crates/ui-egui/src/panels/viewer.rs
+++ b/crates/ui-egui/src/panels/viewer.rs
@@ -1456,10 +1456,16 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                 Gesture::PuppetRecord { layer, pin, others, cti, samples, .. } => {
                     let pts: Vec<serde_json::Value> = samples.iter().map(|(t, p)| json!([t, p[0], p[1]])).collect();
                     let q = json!({"layer": layer.0, "pin": pin, "pins": others, "samples": pts, "start": cti.seconds()});
-                    if let Err(e) = app.session.execute("puppet.recordPin", q) {
-                        app.ui.status = e.to_string();
+                    match app.session.execute("puppet.recordPin", q) {
+                        Ok(_) => {
+                            for p in std::iter::once(pin).chain(others) {
+                                super::puppet_tool::reveal_pin(app, layer, p);
+                            }
+                        }
+                        Err(e) => app.ui.status = e.to_string(),
                     }
                 }
+                Gesture::PuppetPin { layer, pin, .. } => super::puppet_tool::reveal_pin(app, layer, pin),
                 Gesture::Create { tool, start } => {
                     let end = map.to_comp(pos);
                     create_shape(app, tool, start, end, mods.shift);
@@ -1555,9 +1561,13 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     && let Some(inv) = l2c(&ectx, l).0.inverse()
                 {
                     let lp = inv.apply(gv2(cpt[0], cpt[1]));
-                    let r = app.session.execute("puppet.addPin", json!({"layer": l.id.0, "kind": t.puppet_kind(), "position": [lp.x, lp.y]}));
-                    if let Err(e) = r {
-                        app.ui.status = e.to_string();
+                    match app.session.execute("puppet.addPin", json!({"layer": l.id.0, "kind": t.puppet_kind(), "position": [lp.x, lp.y]})) {
+                        Ok(r) => {
+                            if let Some(pin) = r["pin"].as_u64() {
+                                super::puppet_tool::reveal_pin(app, l.id, pin);
+                            }
+                        }
+                        Err(e) => app.ui.status = e.to_string(),
                     }
                 }
             }
diff --git a/crates/ui-egui/src/prefs_live.rs b/crates/ui-egui/src/prefs_live.rs
index 41a4932b..8627c9c6 100644
--- a/crates/ui-egui/src/prefs_live.rs
+++ b/crates/ui-egui/src/prefs_live.rs
@@ -17,9 +17,10 @@ pub fn frame(app: &mut EffectcraftApp, ctx: &egui::Context) {
     video_preview(app, ctx);
 }
 
-/// Files dropped on the window are imported (layered files as Default Drag Import As says).
-/// Dropped on the Composition viewer, they also become layers centred there, as in After
-/// Effects (#85), when the platform reports where the pointer is during file drags.
+/// Files dropped on the window are imported (layered files as Default Drag Import As says) in
+/// the background, with the Importing card showing what is read (#270). Dropped on the
+/// Composition viewer, they also become layers centred there, as in After Effects (#85), when the
+/// platform reports where the pointer is during file drags.
 fn dropped_files(app: &mut EffectcraftApp, ctx: &egui::Context) {
     let paths: Vec<String> =
         ctx.input(|i| i.raw.dropped_files.iter().map(|f| f.path().to_string_lossy().to_string()).filter(|p| std::path::Path::new(p).is_absolute()).collect());
@@ -39,7 +40,8 @@ fn dropped_files(app: &mut EffectcraftApp, ctx: &egui::Context) {
         let viewer = app.auto.find("viewer.area").map(|e| Rect::from_min_size(egui::pos2(e.rect[0], e.rect[1]), egui::vec2(e.rect[2], e.rect[3])));
         let at =
             ctx.input(|i| i.pointer.hover_pos()).filter(|p| viewer.is_some_and(|v| v.contains(*p))).and_then(|p| crate::panels::viewer::screen_to_comp(ctx, p));
-        let params = json!({"paths": rest, "drag": true, "importAs": app.session.prefs.drag_import_as(), "addToComp": at.is_some(), "position": at});
+        let params =
+            json!({"paths": rest, "drag": true, "importAs": app.session.prefs.drag_import_as(), "addToComp": at.is_some(), "position": at, "background": true});
         if let Err(e) = crate::menus::invoke(app, ctx, "file.import", params) {
             app.ui.status = e;
         }
diff --git a/crates/ui-egui/tests/ui_drag_drop.rs b/crates/ui-egui/tests/ui_drag_drop.rs
index b05a235a..7c35f6ec 100644
--- a/crates/ui-egui/tests/ui_drag_drop.rs
+++ b/crates/ui-egui/tests/ui_drag_drop.rs
@@ -1,7 +1,11 @@
 //! Drag and drop between panels (egui_kittest, real pointer drags): Project
 //! items land in the Timeline where they are dropped, between layers and, over the time graph,
 //! starting there (#89); dropped on the Composition viewer they are centred where they land
-//! (#85); an effect dropped on the viewer goes on the layer under the pointer (#88).
+//! (#85); an effect dropped on the viewer goes on the layer under the pointer (#88). Files
+//! dropped on the window import with visible progress (#270).
+
+use std::sync::Arc;
+use std::sync::atomic::{AtomicUsize, Ordering};
 
 use effectcraft_engine::Session;
 use effectcraft_engine::keyframe::Value as KV;
@@ -165,3 +169,91 @@ fn project_items_dropped_on_new_comp_make_a_composition() {
     assert!(h.state().auto.find("form.field.single").is_some(), "the New Composition from Selection dialog");
     assert_eq!(comps(&h), before + 1, "nothing made yet");
 }
+
+/// A file dropped on the window (egui hands it over as a dropped file).
+#[derive(Debug)]
+struct Dropped(std::path::PathBuf);
+
+impl egui::DroppedFile for Dropped {
+    fn path(&self) -> &std::path::Path {
+        &self.0
+    }
+    fn bytes(&self) -> Result<Vec<u8>, String> {
+        Err("not read".into())
+    }
+}
+
+/// Footage probes that hold file k until `allow` > k (slow video decoding), 5 s at most (an
+/// import that blocks the app then fails the test instead of hanging it).
+struct Gated {
+    started: AtomicUsize,
+    allow: Arc<AtomicUsize>,
+}
+
+impl effectcraft_engine::Importer for Gated {
+    fn probe(&self, path: &str) -> Result<effectcraft_engine::project::Footage, String> {
+        let k = self.started.fetch_add(1, Ordering::SeqCst);
+        let until = std::time::Instant::now() + std::time::Duration::from_secs(5);
+        while self.allow.load(Ordering::SeqCst) <= k && std::time::Instant::now() < until {
+            std::thread::sleep(std::time::Duration::from_millis(1));
+        }
+        Ok(effectcraft_engine::project::Footage { path: path.into(), width: 64, height: 32, has_video: true, ..Default::default() })
+    }
+}
+
+/// Step the app until `done` holds (the import runs on another thread).
+fn step_until(h: &mut Harness<'_, EffectcraftApp>, done: impl Fn(&Harness<'_, EffectcraftApp>) -> bool) {
+    let deadline = std::time::Instant::now() + std::time::Duration::from_secs(10);
+    while !done(h) {
+        assert!(std::time::Instant::now() < deadline, "timed out");
+        std::thread::sleep(std::time::Duration::from_millis(2));
+        h.step();
+    }
+}
+
+/// #270: files dropped on the window import in the background with an Importing card that names
+/// the file being read and how many are left (the app keeps drawing meanwhile); then they are
+/// selected and shown in the Project panel, with the count in a toast. The same file dropped
+/// again arrives again, selected.
+#[test]
+fn dropped_files_show_import_progress_then_the_items_they_made() {
+    let (mut h, _) = harness();
+    let allow = Arc::new(AtomicUsize::new(1));
+    h.state_mut().session.importer = Some(Arc::new(Gated { started: AtomicUsize::new(0), allow: allow.clone() }));
+    let file = |n: &str| std::env::temp_dir().join(n);
+    for n in ["a.png", "b.png", "c.png"] {
+        h.input_mut().dropped_files.push(Arc::new(Dropped(file(n))));
+    }
+    h.run_steps(2);
+    let card = |h: &Harness<'_, EffectcraftApp>| h.state().auto.query("import.job.").first().map(|e| e.label.clone());
+    step_until(&mut h, |h| card(h).as_deref() == Some("b.png (2 of 3)"));
+    let r = rect(&h, &card_id(&h));
+    assert!(r.min.x < 40.0 && r.max.y > 960.0, "bottom left, over the panels (where toasts show): {r:?}");
+    assert!(h.state().auto.find(&card_id(&h).replace("import.job.", "import.cancel.")).is_some(), "with Cancel");
+    let items = |h: &Harness<'_, EffectcraftApp>| h.state().session.project.items.values().filter(|i| i.name.ends_with(".png")).count();
+    assert_eq!(items(&h), 0, "nothing added until the import finishes");
+    allow.store(usize::MAX, Ordering::SeqCst);
+    step_until(&mut h, |h| card(h).is_none() && items(h) == 3);
+    h.run_steps(2);
+    let st = &h.state().session.state;
+    let names: Vec<String> = st.project_selection.iter().map(|i| h.state().session.project.item(*i).unwrap().name.clone()).collect();
+    assert_eq!(names, ["a.png", "b.png", "c.png"], "what arrived is selected");
+    let last = st.project_selection[2].0;
+    assert!(h.state().auto.find(&format!("project.item.{last}")).is_some(), "and in view in the Project panel");
+    assert_eq!(h.state().auto.find("toast").map(|e| e.label.as_str()), Some("Imported 3 items"));
+
+    // The same file again: imported again, and that one is selected.
+    h.input_mut().dropped_files.push(Arc::new(Dropped(file("a.png"))));
+    h.run_steps(2);
+    step_until(&mut h, |h| items(h) == 4);
+    h.run_steps(2);
+    let sel = &h.state().session.state.project_selection;
+    assert_eq!(sel.len(), 1);
+    assert_eq!(h.state().session.project.item(sel[0]).unwrap().name, "a.png");
+    assert_eq!(h.state().auto.find("toast").map(|e| e.label.as_str()), Some("Imported 1 item"));
+}
+
+/// The automation id of the Importing card on screen.
+fn card_id(h: &Harness<'_, EffectcraftApp>) -> String {
+    h.state().auto.query("import.job.").first().map(|e| e.id.clone()).unwrap_or_default()
+}
diff --git a/crates/ui-egui/tests/ui_viewer.rs b/crates/ui-egui/tests/ui_viewer.rs
index 4a014ba7..61ea76ef 100644
--- a/crates/ui-egui/tests/ui_viewer.rs
+++ b/crates/ui-egui/tests/ui_viewer.rs
@@ -801,6 +801,96 @@ fn puppet_pin_click_selects_and_delete_removes_only_the_pins() {
     assert!(h.state().session.active_comp().unwrap().layer(LayerId(id)).is_some());
 }
 
+/// A pin's Position property and its keys' times (seconds).
+fn pin_keys(h: &Harness<'_, EffectcraftApp>, layer: u64, pin: u64) -> (u64, Vec<f64>) {
+    let l = h.state().session.active_comp().unwrap().layer(LayerId(layer)).unwrap().clone();
+    let pos = l.props.find_group(pin).unwrap().get("position").unwrap().clone();
+    (pos.uid, pos.keys.iter().map(|k| k.time.seconds()).collect())
+}
+
+/// The keys the Timeline draws for a property, left to right.
+fn timeline_keys(h: &Harness<'_, EffectcraftApp>, prop: u64) -> Vec<Pos2> {
+    let mut ks: Vec<Pos2> =
+        h.state().auto.query(&format!("timeline.key.{prop}.")).iter().map(|e| pos2(e.rect[0] + e.rect[2] / 2.0, e.rect[1] + e.rect[3] / 2.0)).collect();
+    ks.sort_by(|a, b| a.x.total_cmp(&b.x));
+    ks
+}
+
+/// The pin the last click placed (placing a pin selects it).
+fn placed_pin(h: &Harness<'_, EffectcraftApp>) -> u64 {
+    h.state().session.state.selected_props.last().map(|(_, u)| *u).unwrap()
+}
+
+/// #273: U shows each pin's keyframed Position under its pin (Puppet ▸ Mesh 1 ▸ Deform ▸ Puppet
+/// Pin 1 ▸ Position) rather than as one more "Position"; a pin moved or placed in the viewer
+/// afterwards shows its keys there too (they were made but not shown); and pin keys select, move
+/// and delete like any others.
+#[test]
+fn puppet_pin_keys_show_under_their_pins_in_the_timeline() {
+    let (mut h, id, bend) = puppet_harness();
+    h.state_mut().ui.tool = Tool::Puppet;
+    let pins: Vec<u64> = h.state().auto.previous.iter().filter_map(|e| e.id.strip_prefix("viewer.puppetPin.")?.parse().ok()).filter(|p| *p != bend).collect();
+    let ctx = h.ctx.clone();
+    effectcraft_ui_egui::menus::invoke(h.state_mut(), &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    h.run_steps(3);
+    assert_eq!(pins.len(), 2);
+    for pin in &pins {
+        let row = h.state().auto.find(&format!("timeline.group.{pin}.name")).map(|e| e.label.clone()).unwrap_or_default();
+        assert!(row.starts_with("Puppet Pin"), "the pin's row: {row:?}");
+        assert_eq!(timeline_keys(&h, pin_keys(&h, id, *pin).0).len(), 1, "its key at 0 s");
+    }
+    // Moved at 1 s: keyed there, in view.
+    h.state_mut().session.set_time(effectcraft_engine::time::Tick::from_seconds_f64(1.0));
+    h.run_steps(2);
+    let pa = rect(&h, &format!("viewer.puppetPin.{}", pins[0])).center();
+    drag(&mut h, pa, pa + vec2(20.0, 10.0));
+    let (pos, times) = pin_keys(&h, id, pins[0]);
+    assert_eq!(times.len(), 2);
+    assert_eq!(timeline_keys(&h, pos).len(), 2, "both keys drawn");
+    // A pin placed after U shows with its key too.
+    let at = screen(&h, [320.0, 210.0]);
+    click(&mut h, at);
+    let new = placed_pin(&h);
+    assert!(!pins.contains(&new) && new != bend);
+    assert!(h.state().auto.find(&format!("timeline.group.{new}.name")).is_some(), "the new pin's row");
+    assert_eq!(timeline_keys(&h, pin_keys(&h, id, new).0).len(), 1, "and its key");
+    // Click the 1 s key, drag it half a second later, delete it.
+    let ks = timeline_keys(&h, pos);
+    click(&mut h, ks[1]);
+    assert_eq!(h.state().session.state.selected_keys.iter().map(|k| k.prop).collect::<Vec<_>>(), [pos]);
+    let half = (ks[1].x - ks[0].x) / 2.0;
+    drag(&mut h, ks[1], ks[1] + vec2(half, 0.0));
+    let t = pin_keys(&h, id, pins[0]).1;
+    assert!((t[1] - 1.5).abs() < 0.05, "moved: {t:?}");
+    h.input_mut().events.push(Event::Key { key: egui::Key::Delete, physical_key: None, pressed: true, repeat: false, modifiers: Default::default() });
+    h.run_steps(2);
+    assert_eq!(pin_keys(&h, id, pins[0]).1, [0.0], "deleted; the pin stays");
+}
+
+/// #273: on a layer twirled open in the Timeline, placing a pin twirls open Effects ▸ Puppet ▸
+/// Mesh 1 ▸ Deform ▸ the pin, so its Position key shows; a collapsed layer stays collapsed, as
+/// in After Effects.
+#[test]
+fn placing_a_pin_opens_its_groups_on_a_twirled_open_layer() {
+    let mut h = harness();
+    let s = &mut h.state_mut().session;
+    s.execute("edit.clear", json!({"layers": ["Plate"]})).unwrap();
+    s.execute("layer.select", json!({"layers": ["Box"]})).unwrap();
+    let id = s.state.selected_layers[0].0;
+    h.state_mut().ui.tool = Tool::Puppet;
+    h.run_steps(2);
+    let at = screen(&h, [300.0, 160.0]);
+    click(&mut h, at);
+    assert!(h.state().ui.timeline.open_groups.is_empty() && h.state().ui.timeline.open_layers.is_empty(), "collapsed stays collapsed");
+    let twirl = rect(&h, &format!("timeline.layer.{id}.twirl")).center();
+    click(&mut h, twirl);
+    assert!(h.state().ui.timeline.open_layers.contains(&id));
+    let at = screen(&h, [340.0, 200.0]);
+    click(&mut h, at);
+    let pin = placed_pin(&h);
+    assert_eq!(timeline_keys(&h, pin_keys(&h, id, pin).0).len(), 1, "the new pin's Position key shows");
+}
+
 /// Filled circles painted this frame (flattening nested shape lists).
 fn circles(h: &Harness<'_, EffectcraftApp>) -> Vec<egui::epaint::CircleShape> {
     fn walk(s: &egui::Shape, out: &mut Vec<egui::epaint::CircleShape>) {