diff --git a/crates/engine/src/cmd/edit/props.rs b/crates/engine/src/cmd/edit/props.rs
index 8724f267..8156d072 100644
--- a/crates/engine/src/cmd/edit/props.rs
+++ b/crates/engine/src/cmd/edit/props.rs
@@ -393,7 +393,8 @@ pub(super) fn paint_paste(s: &mut Session, p: &Value, fills: bool) -> Result<Val
             // The destination may already use that key for different data (other layers keep
             // that image): the pasted paint takes the copied data's content hash instead. That key
             // can be taken too — images are usually keyed by their hash, so the copied key often
-            // is that hash — and then a numbered variant of it.
+            // is that hash — and then a numbered variant of it. Image keys become archive member
+            // names, which keep only letters and digits, so the number is appended plainly.
             let base = if doc.images.get(&copied).is_some_and(|existing| existing != &d) { figcraft_format::image_hash(&d.bytes) } else { copied };
             let mut key = base.clone();
             let mut n = 0u32;
@@ -402,7 +403,7 @@ pub(super) fn paint_paste(s: &mut Session, p: &Value, fills: bool) -> Result<Val
                 if n > 999 {
                     return Err(bad(cmd, "no free image key for the copied image"));
                 }
-                key = format!("{base}-{n}");
+                key = format!("{base}{n}");
             }
             doc.images.entry(key.clone()).or_insert(d);
             img.image = key;
diff --git a/crates/engine/src/property_copy_tests.rs b/crates/engine/src/property_copy_tests.rs
index 0d85901f..160dfaaf 100644
--- a/crates/engine/src/property_copy_tests.rs
+++ b/crates/engine/src/property_copy_tests.rs
@@ -165,6 +165,22 @@ fn a_copied_image_whose_hash_key_is_also_taken_gets_a_free_key() {
     assert_ne!(img.image, hash, "the taken hash is not reused");
     assert_eq!(doc.images.get(&img.image), Some(&copied), "the pasted paint points at the copied data");
     assert_eq!(doc.images.get(&hash), Some(&taken), "the destination's image stays");
+    let key = img.image.clone();
+    // An image key names an archive member, and only letters and digits are read back: the
+    // numbered key must bring the copied image through a save and reopen.
+    assert!(key.bytes().all(|b| b.is_ascii_alphanumeric()), "the key is archive-valid: {key}");
+    let dir = std::env::temp_dir().join(format!("figcraft-image-key-{}", std::process::id()));
+    std::fs::create_dir_all(&dir).unwrap();
+    let path = dir.join("pasted.figcraft").to_string_lossy().to_string();
+    ex(&mut s, "file.save", json!({"path": path}));
+    let mut t = Session::empty();
+    ex(&mut t, "file.open", json!({"path": path}));
+    let saved = t.doc().unwrap();
+    let figcraft_color::PaintKind::Image(img) = &saved.node(b).unwrap().fills[0].kind else { panic!("the pasted fill is an image") };
+    assert_eq!(img.image, key, "the reloaded paint keeps its key");
+    // A reopened image's size is read from its pixels on demand, so only its bytes are compared.
+    assert_eq!(saved.images.get(&key).map(|i| i.bytes.as_slice()), Some(copied.bytes.as_slice()), "the copied image survives the reload");
+    let _ = std::fs::remove_dir_all(&dir);
 }
 
 #[test]
diff --git a/crates/ui-egui/src/panels/right/menu.rs b/crates/ui-egui/src/panels/right/menu.rs
index 8161d20a..db3820c5 100644
--- a/crates/ui-egui/src/panels/right/menu.rs
+++ b/crates/ui-egui/src/panels/right/menu.rs
@@ -1,4 +1,4 @@
-use super::{BlendMode, Color32, CornerRadius, FIELD_H, Id, PAD, Rect, Sense, Tokens, Ui, a11y, pos2, regular, tr, vec2};
+use super::{BlendMode, Color32, CornerRadius, FIELD_H, FigApp, Id, NodeId, PAD, Rect, Sense, Tokens, Ui, a11y, json, pos2, regular, tr, vec2};
 
 /// The smallest width a popup menu is measured in (see [`menu_popup`]).
 const MENU_MIN_W: f32 = 48.0;
@@ -14,11 +14,6 @@ pub(crate) fn menu_style(s: &mut egui::Style) {
     s.wrap_mode = Some(egui::TextWrapMode::Extend);
 }
 
-/// The menu a dropdown or button opens: as wide as its widest row and at least as wide as
-/// `anchor`. egui measures a popup in a first, invisible pass as wide as the width it is given
-/// (else its 600 px default area width) and keeps the size measured; rows ([`menu_row`]) take the
-/// larger of that width and their content, so the menu fits its content. Chain `.width(w)` for a
-/// menu at least `w` wide.
 /// The blend modes as menu items in groups (pass-through only for layers); the one picked. Each
 /// row `preview`s its mode on the canvas while hovered.
 pub fn blend_menu(ui: &mut Ui, with_pass_through: bool, mut preview: impl FnMut(BlendMode)) -> Option<BlendMode> {
@@ -44,6 +39,11 @@ pub(crate) fn preview_blend(app: &mut FigApp, ctx: &egui::Context, ids: &[NodeId
     app.preview_text(ctx, "node.set", json!({"ids": ids, "props": {"blend": blend.label()}}));
 }
 
+/// The menu a dropdown or button opens: as wide as its widest row and at least as wide as
+/// `anchor`. egui measures a popup in a first, invisible pass as wide as the width it is given
+/// (else its 600 px default area width) and keeps the size measured; rows ([`menu_row`]) take the
+/// larger of that width and their content, so the menu fits its content. Chain `.width(w)` for a
+/// menu at least `w` wide.
 pub fn menu_popup(anchor: &egui::Response) -> egui::Popup<'static> {
     egui::Popup::menu(anchor).width(anchor.rect.width().max(MENU_MIN_W)).style(menu_style)
 }