From f31a6b0aef5fcc3bbab5f8ee1a2643f7fff7ec02 Mon Sep 17 00:00:00 2001
From: "Dylan M. Taylor" <dylan@dylanmtaylor.com>
Date: Sun, 25 Oct 2026 19:37:04 -0400
Subject: [PATCH] sonar: optional chaining (S6582) and for-of loops (S4138) in
 engine-owned JS (#2273)

ExtendScript .jsx files are left alone (ES3, no ?. or for-of).
---
 apps/effectcraft-web/js/host.js      | 28 ++++++------
 apps/effectcraft-web/tests/smoke.mjs | 16 +++----
 crates/expr/src/prelude.js           |  8 ++--
 crates/script/src/prelude.js         | 68 ++++++++++++++--------------
 crates/script/src/scriptui.js        | 66 +++++++++++++--------------
 5 files changed, 93 insertions(+), 93 deletions(-)

diff --git a/apps/effectcraft-web/js/host.js b/apps/effectcraft-web/js/host.js
index 12cb90bf..9346acc2 100644
--- a/apps/effectcraft-web/js/host.js
+++ b/apps/effectcraft-web/js/host.js
@@ -19,7 +19,7 @@ const enc = (k) => encodeURIComponent(k);
 const dec = (n) => decodeURIComponent(n);
 
 async function opfs() {
-  if (!navigator.storage || !navigator.storage.getDirectory) throw new Error("no OPFS");
+  if (!navigator.storage?.getDirectory) throw new Error("no OPFS");
   const root = await navigator.storage.getDirectory();
   const dir = await root.getDirectoryHandle(DIR, { create: true });
   // Probe a write: some browsers expose OPFS but only write it from workers.
@@ -116,7 +116,7 @@ export async function storeOpen(prefer) {
     try { backend = await make(); break; } catch (e) { console.info(`storage: ${make.name}: ${e.message ?? e}`); }
   }
   // Ask the browser not to evict the store under storage pressure (granted for installed apps).
-  try { if (navigator.storage && navigator.storage.persist) await navigator.storage.persist(); } catch {}
+  try { if (navigator.storage?.persist) await navigator.storage.persist(); } catch {}
   return backend.name;
 }
 
@@ -128,7 +128,7 @@ export async function storeDelete(key) { return backend.del(key); }
 /// Ask the browser to keep the origin's storage under pressure; resolves with whether it is.
 export async function storePersist() {
   try {
-    if (navigator.storage && navigator.storage.persist) return await navigator.storage.persist();
+    if (navigator.storage?.persist) return await navigator.storage.persist();
   } catch {}
   return false;
 }
@@ -227,7 +227,7 @@ export async function audioStart(workletUrl) {
       }
       if (gen !== generation) return;
       node = new AudioWorkletNode(c, "effectcraft-output", { numberOfInputs: 0, outputChannelCount: [2] });
-      node.port.onmessage = (e) => { if (e.data && e.data.underrun) underruns += e.data.underrun; };
+      node.port.onmessage = (e) => { if (e.data?.underrun) underruns += e.data.underrun; };
       kind = "worklet";
     } catch (e) {
       console.warn("audio: AudioWorklet unavailable, using ScriptProcessorNode", e);
@@ -318,11 +318,11 @@ function spawn(base) {
   const w = { worker, files: new Map(), ready: null, gpu: null };
   w.ready = new Promise((res, rej) => {
     worker.onmessage = (e) => {
-      if (e.data && e.data.type === "gpu") {
+      if (e.data?.type === "gpu") {
         w.gpu = e.data.gpu ? { adapter: e.data.gpu } : { cpu: e.data.error || "no GPU" };
         jobGpu = w.gpu;
       }
-      if (e.data && e.data.type === "ready") res();
+      if (e.data?.type === "ready") res();
     };
     worker.onerror = (e) => rej(new Error(e.message || "worker failed to start"));
   });
@@ -341,7 +341,7 @@ export function workerRun(id, json, files, base, onMessage) {
   } catch (e) {
     // `new Worker` throws at once when the page's origin is opaque (a sandboxed iframe): the job
     // fails like one whose worker didn't start.
-    setTimeout(() => onMessage("error", String((e && e.message) || e), null, null));
+    setTimeout(() => onMessage("error", String(e?.message || e), null, null));
     return;
   }
   running.set(id, w);
@@ -416,12 +416,12 @@ export function frameWorkerStart(base, onMessage, gpu) {
     // slot stays, and the failure is reported like a worker that died, after the caller has
     // recorded the index: frames then render on the page's thread (as with `?noworkers`).
     frameWorkers.push(null);
-    setTimeout(() => onMessage(index, undefined, undefined, String((e && e.message) || e || "frame worker failed")));
+    setTimeout(() => onMessage(index, undefined, undefined, String(e?.message || e || "frame worker failed")));
     return index;
   }
   worker.onmessage = (e) => {
     const m = e.data;
-    if (m && m.type === "frameReply") onMessage(index, m.json, m.bytes ? new Uint8Array(m.bytes) : null, undefined);
+    if (m?.type === "frameReply") onMessage(index, m.json, m.bytes ? new Uint8Array(m.bytes) : null, undefined);
   };
   worker.onerror = (e) => {
     onMessage(index, undefined, undefined, String(e.message || "frame worker failed"));
@@ -447,7 +447,7 @@ const cacheDirHandles = {};
 
 async function cacheDir(kind = "frames") {
   if (cacheDirHandles[kind]) return cacheDirHandles[kind];
-  if (!navigator.storage || !navigator.storage.getDirectory) throw new Error("no Origin Private File System");
+  if (!navigator.storage?.getDirectory) throw new Error("no Origin Private File System");
   let d = await navigator.storage.getDirectory();
   for (const n of [CACHE_ROOT, "v1", kind]) d = await d.getDirectoryHandle(n, { create: true });
   cacheDirHandles[kind] = d;
@@ -544,7 +544,7 @@ export async function cacheClear() {
 
 /// Whether this thread has WebGPU (`navigator.gpu`).
 export function hasWebGpu() {
-  return !!(self.navigator && self.navigator.gpu);
+  return !!self.navigator?.gpu;
 }
 
 /// Post a message ({type: "frame", json} or {type: "file", path, bytes}) to frame worker `index`.
@@ -652,7 +652,7 @@ export async function browseForget(name) {
 export async function browseRead(path) {
   const rel = path.replace(/^\/Folders\//, "");
   const folder = folders.get(rel.split("/")[0]);
-  const h = folder && folder.files.get(rel);
+  const h = folder?.files.get(rel);
   if (!h) throw new Error(`${path}: its folder is not open (reconnect it)`);
   return new Uint8Array(await (await h.getFile()).arrayBuffer());
 }
@@ -706,7 +706,7 @@ export function showDeviceLost(message, kept) {
     self.effectcraft
       .execute("file.save", {})
       .catch(() => self.effectcraft.execute("file.saveAs", { path: "/Untitled Project.ecproj" }))
-      .catch((e) => (text.textContent = `Saving failed: ${(e && e.message) || e}`));
+      .catch((e) => (text.textContent = `Saving failed: ${e?.message || e}`));
   const reload = document.createElement("button");
   reload.textContent = "Reload";
   reload.onclick = async () => {
@@ -714,7 +714,7 @@ export function showDeviceLost(message, kept) {
     try {
       await self.effectcraft.flush();
     } catch (e) {
-      text.textContent = `Writing to browser storage failed (${(e && e.message) || e}). Save the project, or reload anyway and lose the changes.`;
+      text.textContent = `Writing to browser storage failed (${e?.message || e}). Save the project, or reload anyway and lose the changes.`;
       reload.textContent = "Reload Anyway";
       reload.disabled = false;
       reload.onclick = () => location.reload();
diff --git a/apps/effectcraft-web/tests/smoke.mjs b/apps/effectcraft-web/tests/smoke.mjs
index 3a6c1337..83091a72 100644
--- a/apps/effectcraft-web/tests/smoke.mjs
+++ b/apps/effectcraft-web/tests/smoke.mjs
@@ -162,7 +162,7 @@ try {
   const info = await js("effectcraft.info()");
   report.steps.gpu = { webgpu: info.webgpu, backend: info.backend, ...info.gpu };
   if (info.webgpu && info.backend === "BrowserWebGpu") {
-    check(info.gpu && info.gpu.compositor, "GPU compositor on WebGPU");
+    check(info.gpu?.compositor, "GPU compositor on WebGPU");
     check(info.gpu.viewerOnGpu, "viewer frames on the GPU");
   }
 
@@ -250,7 +250,7 @@ try {
   const st = await js(`(async () => { await new Promise((r) => setTimeout(r, 1200)); return effectcraft.execute("storage.info", {}); })()`);
   report.steps.storage = st;
   check(st.available && st.quota > 0 && st.usage > 0, `storage.info: ${JSON.stringify(st)}`);
-  check(st.diskCache && st.diskCache.enabled && st.diskCache.writes > 0, `disk cache in OPFS: ${JSON.stringify(st.diskCache)}`);
+  check(st.diskCache?.enabled && st.diskCache.writes > 0, `disk cache in OPFS: ${JSON.stringify(st.diskCache)}`);
   await js(`effectcraft.execute("prefs.open", {page: "disk"})`);
   await sleep(800);
   report.steps.storage.screenshot = await shot("01c-storage-manager");
@@ -378,14 +378,14 @@ try {
     const jobs = gj.workers.jobs || [];
     const rj = jobs.filter((j) => j.kind === "Render").pop();
     const wj = jobs.filter((j) => j.kind === "Warp").pop();
-    check(gj.workers.gpu && gj.workers.gpu.adapter, `job workers have a GPU: ${JSON.stringify(gj.workers)}`);
+    check(gj.workers.gpu?.adapter, `job workers have a GPU: ${JSON.stringify(gj.workers)}`);
     check(gj.status.every((st) => st === "Done"), `GPU job render: ${JSON.stringify(gj.status)}`);
-    check(rj && rj.gpu && rj.readbacks >= 3 && rj.passes >= 6, `Render Queue frames on the job worker's GPU, in passes: ${JSON.stringify(rj)}`);
+    check(rj?.gpu && rj.readbacks >= 3 && rj.passes >= 6, `Render Queue frames on the job worker's GPU, in passes: ${JSON.stringify(rj)}`);
     check(gj.warp.analyzed, `Warp Stabilizer analysed in a job worker: ${JSON.stringify(gj.warp)}`);
-    check(wj && wj.gpu && wj.readbacks > 0, `Warp Stabilizer input frames on the job worker's GPU: ${JSON.stringify(wj)}`);
+    check(wj?.gpu && wj.readbacks > 0, `Warp Stabilizer input frames on the job worker's GPU: ${JSON.stringify(wj)}`);
     const fj = jobs.filter((j) => j.kind === "ContentFill").pop();
     check(!gj.fill.error && gj.fillLayers.length > 0, `Content-Aware Fill in a job worker: ${JSON.stringify(gj.fill)} ${JSON.stringify(gj.fillLayers)}`);
-    check(fj && fj.gpu && fj.readbacks > 0, `Content-Aware Fill frames on the job worker's GPU: ${JSON.stringify(fj)}`);
+    check(fj?.gpu && fj.readbacks > 0, `Content-Aware Fill frames on the job worker's GPU: ${JSON.stringify(fj)}`);
     check(gj.maxGapMs < 400, `event loop blocked ${gj.maxGapMs} ms during the GPU jobs: ${JSON.stringify(gj.gaps)}`);
     check(gj.gaps.prepareFill < 50, `event loop blocked ${gj.gaps.prepareFill} ms while editing after the analysis (pre-compose, mask): ${JSON.stringify(gj.gaps)}`);
   } else {
@@ -418,7 +418,7 @@ try {
   check(mb.path === "/Browser Storage" && mb.entries.some((e) => e.name === "tone.wav" && e.kind === "audio"), `Media Browser: ${JSON.stringify(report.steps.mediaBrowser)}`);
   check(mb.actions.some((a) => a.id === "addFiles"), "Media Browser: Add Files…");
   const mbImport = await js(`effectcraft.execute("mediaBrowser.import", {paths: [${JSON.stringify(mb.entries.find((e) => e.name === "tone.wav")?.path ?? "/tone.wav")}]})`);
-  check(!mbImport.pending && mbImport.items && mbImport.items.length === 1, `Media Browser import: ${JSON.stringify(mbImport)}`);
+  check(!mbImport.pending && mbImport.items?.length === 1, `Media Browser import: ${JSON.stringify(mbImport)}`);
   await js(`effectcraft.request("ui.playback", {action: "stop"})`);
   await js(`effectcraft.execute("time.set", {time: 0})`);
   await js(`effectcraft.request("ui.playback", {action: "play"})`);
@@ -579,7 +579,7 @@ try {
   report.steps.final2 = { screenshot: await shot("03-offline") };
 } catch (e) {
   failed = true;
-  report.error = String(e && e.stack || e);
+  report.error = String(e?.stack || e);
   try { report.errorShot = await shot("error"); } catch {}
 }
 report.console = logs.slice(-40);
diff --git a/crates/expr/src/prelude.js b/crates/expr/src/prelude.js
index df6ed3ff..6611d36a 100644
--- a/crates/expr/src/prelude.js
+++ b/crates/expr/src/prelude.js
@@ -840,14 +840,14 @@ var __propHandler = {
     // A layer-valued property (a Layer Control's Layer) is named as its layer (#809).
     if (k === 'name' && t.__info[2] === 'layer') {
       var lv = t.value;
-      if (lv !== null && lv !== undefined && lv.__isLayer) return lv.name;
+      if (lv?.__isLayer) return lv.name;
     }
     if (k in t) return t[k];
     var v = t.value;
     if (v === null || v === undefined) return undefined;
     var x = v[k];
     // Property groups are callable proxies: hand them over as they are, not bound like methods (#809).
-    if (x !== null && x !== undefined && x.__isGroup) return x;
+    if (x?.__isGroup) return x;
     return typeof x === 'function' ? x.bind(v) : x;
   },
 };
@@ -904,8 +904,8 @@ __TextStyle.prototype = {
   },
   get text() {
     var t = this.__d.text;
-    for (var k = 0; k < this.__ops.length; k++) {
-      var o = this.__ops[k];
+    for (const elem of this.__ops) {
+      var o = elem;
       if (o[0] !== 'text') continue;
       if (o[2] < 0) t = String(o[1]);
       else t = t.slice(0, o[2]) + String(o[1]) + (o[3] < 0 ? '' : t.slice(o[2] + o[3]));
diff --git a/crates/script/src/prelude.js b/crates/script/src/prelude.js
index 5216db34..ce64e221 100644
--- a/crates/script/src/prelude.js
+++ b/crates/script/src/prelude.js
@@ -420,7 +420,7 @@ function __callable(o) {
   delete f.length;
   Object.setPrototypeOf(f, Object.getPrototypeOf(o));
   var keys = Object.keys(o);
-  for (var i = 0; i < keys.length; i++) f[keys[i]] = o[keys[i]];
+  for (const elem of keys) f[elem] = o[elem];
   var self = new Proxy(f, {
     get: __attr.get,
     apply: function (t, thisArg, args) { return self.property(args[0]); },
@@ -473,7 +473,7 @@ function MarkerValue(comment, chapter, url, frameTarget, cuePointName, params) {
 }
 MarkerValue.prototype.getParameters = function () {
   var o = {};
-  for (var i = 0; i < this.__params.length; i++) o[this.__params[i][0]] = this.__params[i][1];
+  for (const elem of this.__params) o[elem[0]] = elem[1];
   return o;
 };
 MarkerValue.prototype.setParameters = function (o) {
@@ -513,8 +513,8 @@ TextDocument.prototype = {
   set text(v) { this.__text = String(v); this.__textSet = true; },
   __style: function (k, d) {
     if (k in this.__changed) return this.__changed[k];
-    if (this.__base && this.__base.first && k in this.__base.first) return this.__base.first[k];
-    if (this.__base && this.__base.para && k in this.__base.para) return this.__base.para[k];
+    if (this.__base?.first && k in this.__base.first) return this.__base.first[k];
+    if (this.__base?.para && k in this.__base.para) return this.__base.para[k];
     return d;
   },
   __set: function (k, v) { this.__changed[k] = v; },
@@ -580,14 +580,14 @@ TextDocument.prototype = {
   },
   get tsume() { return this.__style("tsume", 0); },
   set tsume(v) { this.__set("tsume", __num(v)); },
-  get boxText() { return !!(this.__base && this.__base.box_size); },
+  get boxText() { return !!this.__base?.box_size; },
   get pointText() { return !this.boxText; },
-  get boxTextSize() { return this.__base && this.__base.box_size ? this.__base.box_size.slice() : undefined; },
+  get boxTextSize() { return this.__base?.box_size ? this.__base.box_size.slice() : undefined; },
   set boxTextSize(v) {
     var p = this.boxTextPos || [0, 0];
     this.__set("box", [p[0], p[1], v[0], v[1]]);
   },
-  get boxTextPos() { return this.__base && this.__base.box_size ? this.__base.box_pos.slice() : undefined; },
+  get boxTextPos() { return this.__base?.box_size ? this.__base.box_pos.slice() : undefined; },
   get startIndent() { return this.__style("indentLeft", 0); },
   set startIndent(v) { this.__set("indentLeft", __num(v)); },
   get endIndent() { return this.__style("indentRight", 0); },
@@ -665,7 +665,7 @@ PropertyBase.prototype = {
   get isMask() { return !!this.__info().isMask; },
   get selected() {
     var c = __get("item", { id: this.__layer.__comp }).selectedProperties;
-    for (var i = 0; i < c.length; i++) if (c[i][0] === this.__layer.__id && c[i][1] === this.__uid) return true;
+    for (const elem of c) if (elem[0] === this.__layer.__id && elem[1] === this.__uid) return true;
     return false;
   },
   set selected(v) {
@@ -842,7 +842,7 @@ Property.prototype.property = function () { return null; };
     i = __num(i, "keyIndex");
     // Only the key asked for: fetching the whole list made every key call linear (#814).
     var r = i >= 1 && Math.floor(i) === i ? __get("keys", { comp: this.__layer.__comp, layer: this.__layer.__id, uid: this.__uid, index: i - 1 }) : null;
-    if (!r || !r.key) throw __err("keyIndex " + i + " is out of range 1.." + (r ? r.count : this.numKeys));
+    if (!r?.key) throw __err("keyIndex " + i + " is out of range 1.." + (r ? r.count : this.numKeys));
     return r.key;
   };
   // Script value → engine JSON for `prop.set` / `prop.addKey`.
@@ -853,13 +853,13 @@ Property.prototype.property = function () { return null; };
       return __get("textdoc", { comp: this.__layer.__comp, layer: this.__layer.__id, uid: this.__uid, time: time, attrs: td.__attrs() });
     }
     if (t === "SHAPE") {
-      if (!v || !v.vertices) throw __err("value must be a Shape");
+      if (!v?.vertices) throw __err("value must be a Shape");
       var n = v.vertices.length;
-      function fit(a) { var o = []; for (var i = 0; i < n; i++) o.push(a && a[i] ? [a[i][0], a[i][1]] : [0, 0]); return o; }
+      function fit(a) { var o = []; for (var i = 0; i < n; i++) o.push(a?.[i] ? [a[i][0], a[i][1]] : [0, 0]); return o; }
       return { vertices: fit(v.vertices), in_tangents: fit(v.inTangents), out_tangents: fit(v.outTangents), closed: v.closed !== false };
     }
     if (t === "LAYER_INDEX") {
-      var idx = v && v.__id !== undefined ? v.index : __num(v);
+      var idx = v?.__id !== undefined ? v.index : __num(v);
       if (!idx) return null;
       return this.__layer.containingComp.layer(idx).__id;
     }
@@ -1177,7 +1177,7 @@ Layer.prototype = {
   },
   get selectedProperties() {
     var c = this.containingComp.__info().selectedProperties, out = [];
-    for (var i = 0; i < c.length; i++) if (c[i][0] === this.__id) out.push(__propOf(this, __get("node", { comp: this.__comp, layer: this.__id, uid: c[i][1] })));
+    for (const elem of c) if (elem[0] === this.__id) out.push(__propOf(this, __get("node", { comp: this.__comp, layer: this.__id, uid: elem[1] })));
     return out;
   },
   get parent() { var p = this.__info().parent; return p === null ? null : __layer(this.__comp, p); },
@@ -1205,7 +1205,7 @@ Layer.prototype = {
     var before = this.containingComp.__info().layers;
     __call("edit.duplicate", this.__p());
     var after = this.containingComp.__info().layers;
-    for (var i = 0; i < after.length; i++) if (before.indexOf(after[i]) < 0) return __layer(this.__comp, after[i]);
+    for (const elem of after) if (before.indexOf(elem) < 0) return __layer(this.__comp, elem);
     return null;
   },
   copyToComp: function (comp) {
@@ -1310,7 +1310,7 @@ AVLayer.prototype.constructor = AVLayer;
   // AVLayer.replaceSource). `fixExpressions` is accepted for compatibility: only AV sources are
   // replaced, so the property tree and the layer's name stay and expressions keep resolving.
   P.replaceSource = function (newSource, fixExpressions) {
-    if (!newSource || newSource.__id === undefined) throw __err("replaceSource needs a project item");
+    if (newSource?.__id === undefined) throw __err("replaceSource needs a project item");
     __call("layer.replaceSource", { comp: this.__comp, layers: [this.__id], item: newSource.__id, fixExpressions: !!fixExpressions });
     return null;
   };
@@ -1371,7 +1371,7 @@ LayerCollection.prototype = {
     return layer;
   },
   add: function (item, duration) {
-    if (!item || item.id === undefined) throw __err("add(): expected an item");
+    if (item?.id === undefined) throw __err("add(): expected an item");
     var l = this.__new(__call("layer.addItem", { comp: this.__comp, item: item.id, time: 0 }));
     return this.__dur(l, duration);
   },
@@ -1414,15 +1414,15 @@ LayerCollection.prototype = {
   },
   precompose: function (indices, name, moveAllAttributes) {
     var ids = this.__ids(), sel = [];
-    for (var i = 0; i < indices.length; i++) sel.push(ids[indices[i] - 1]);
+    for (const elem of indices) sel.push(ids[elem - 1]);
     var r = __call("layer.precompose", { comp: this.__comp, layers: sel, name: String(name), mode: moveAllAttributes === false ? "leave" : "move" });
     return __item(r.comp);
   },
   byName: function (name) {
     var ids = this.__ids();
-    for (var i = 0; i < ids.length; i++) {
-      var l = __get("layer", { comp: this.__comp, layer: ids[i] });
-      if (l.name === name) return __layer(this.__comp, ids[i]);
+    for (const elem of ids) {
+      var l = __get("layer", { comp: this.__comp, layer: elem });
+      if (l.name === name) return __layer(this.__comp, elem);
     }
     return null;
   },
@@ -1493,7 +1493,7 @@ Item.prototype = {
   get label() { return this.__info().label; },
   set label(v) { __call("project.setLabel", { items: [this.__id], label: __num(v, "label") }); },
   get parentFolder() { return __item(this.__info().parent); },
-  set parentFolder(f) { __call("project.move", { items: [this.__id], folder: f && f.__id ? f.__id : null }); },
+  set parentFolder(f) { __call("project.move", { items: [this.__id], folder: f?.__id ? f.__id : null }); },
   get selected() { return this.__info().selected; },
   set selected(v) {
     var selection = __get("project").selection;
@@ -1527,7 +1527,7 @@ AVItem.prototype = Object.create(Item.prototype);
   def("hasVideo", function () { return this.__info().hasVideo; });
   def("hasAudio", function () { return this.__info().hasAudio; });
   def("footageMissing", function () { return !!this.__info().footageMissing; });
-  def("useProxy", function () { var p = this.__info().proxy; return !!(p && p.enabled); }, function (v) {
+  def("useProxy", function () { var p = this.__info().proxy; return !!p?.enabled; }, function (v) {
     if (!this.__info().proxy) throw __err("\"" + this.name + "\" has no proxy");
     __call("file.useProxy", { item: this.__id, on: !!v });
   });
@@ -1564,9 +1564,9 @@ CompItem.prototype.constructor = CompItem;
   });
   def("activeCamera", function () {
     var ids = this.__info().layers;
-    for (var i = 0; i < ids.length; i++) {
-      var l = __get("layer", { comp: this.__id, layer: ids[i] });
-      if (l.kind === "camera" && l.enabled && l.active) return __layer(this.__id, ids[i]);
+    for (const elem of ids) {
+      var l = __get("layer", { comp: this.__id, layer: elem });
+      if (l.kind === "camera" && l.enabled && l.active) return __layer(this.__id, elem);
     }
     return null;
   });
@@ -1606,7 +1606,7 @@ CompItem.prototype.constructor = CompItem;
       if (a < 1 || a > ids.length || Math.floor(a) !== a) throw __err("layer index " + a + " is out of range 1.." + ids.length);
       return __layer(this.__id, ids[a - 1]);
     }
-    if (a && a.__id !== undefined && typeof b === "number") {
+    if (a?.__id !== undefined && typeof b === "number") {
       var j = a.index + b;
       return j >= 1 && j <= ids.length ? __layer(this.__id, ids[j - 1]) : null;
     }
@@ -1619,9 +1619,9 @@ CompItem.prototype.constructor = CompItem;
   P.__controllers = function () {
     var out = [];
     (function walk(list) {
-      for (var i = 0; i < list.length; i++) {
-        if (list[i].kind === "property" || list[i].kind === "mirror" || list[i].kind === "media") out.push(list[i]);
-        if (list[i].children) walk(list[i].children);
+      for (const elem of list) {
+        if (elem.kind === "property" || elem.kind === "mirror" || elem.kind === "media") out.push(elem);
+        if (elem.children) walk(elem.children);
       }
     })(this.__eg().controls);
     return out;
@@ -1732,7 +1732,7 @@ FolderItem.prototype.constructor = FolderItem;
   Object.defineProperty(P, "numItems", { get: function () { return new ItemCollection(this.__id).length; } });
   Object.defineProperty(P, "parentFolder", {
     get: function () { return this.__id === 0 ? null : __item(this.__info().parent); },
-    set: function (f) { __call("project.move", { items: [this.__id], folder: f && f.__id ? f.__id : null }); },
+    set: function (f) { __call("project.move", { items: [this.__id], folder: f?.__id ? f.__id : null }); },
   });
   P.item = function (i) {
     var v = new ItemCollection(this.__id).__at(__num(i, "index"));
@@ -1776,7 +1776,7 @@ RenderQueueItem.prototype = {
   constructor: RenderQueueItem,
   __info: function () {
     var l = __call("renderQueue.list", {}).items;
-    for (var i = 0; i < l.length; i++) if (l[i].id === this.__id) return l[i];
+    for (const elem of l) if (elem.id === this.__id) return elem;
     throw __err("the render queue item no longer exists");
   },
   get comp() { return __item(this.__info().comp); },
@@ -1812,7 +1812,7 @@ RenderQueueItem.prototype = {
     var before = __call("renderQueue.list", {}).items.map(function (i) { return i.id; });
     __call("renderQueue.duplicate", { item: this.__id });
     var after = __call("renderQueue.list", {}).items;
-    for (var i = 0; i < after.length; i++) if (before.indexOf(after[i].id) < 0) return new RenderQueueItem(after[i].id);
+    for (const elem of after) if (before.indexOf(elem.id) < 0) return new RenderQueueItem(elem.id);
     return null;
   },
   applyTemplate: function () {},
@@ -1945,9 +1945,9 @@ Project.prototype = {
       }
     }
     var r = __call("file.import", args);
-    if (r.errors && r.errors.length) throw __err(r.errors.join("; "));
+    if (r.errors?.length) throw __err(r.errors.join("; "));
     // Composition imports create several footage items, but callers need the comp.
-    return __item(r.comps && r.comps.length ? r.comps[0] : r.items[0]);
+    return __item(r.comps?.length ? r.comps[0] : r.items[0]);
   },
   importFileWithDialog: function () { return null; },
   importPlaceholder: function (name, w, h, rate, dur) {
diff --git a/crates/script/src/scriptui.js b/crates/script/src/scriptui.js
index 52c65efb..4760d058 100644
--- a/crates/script/src/scriptui.js
+++ b/crates/script/src/scriptui.js
@@ -213,7 +213,7 @@ function __uiResPlain(v) {
   if (v instanceof Array) return v.map(__uiResPlain);
   if (v && typeof v === "object" && v.__object) {
     var o = {};
-    for (var k = 0; k < v.__object.length; k++) o[v.__object[k][0]] = __uiResPlain(v.__object[k][1]);
+    for (const elem of v.__object) o[elem[0]] = __uiResPlain(elem[1]);
     return o;
   }
   return v;
@@ -222,8 +222,8 @@ function __uiResPlain(v) {
 // A resource's own properties and its child elements (in source order).
 function __uiResProps(res) {
   var props = {}, kids = [];
-  for (var k = 0; k < res.list.length; k++) {
-    var e = res.list[k];
+  for (const elem2 of res.list) {
+    var e = elem2;
     if (e[1] && typeof e[1] === "object" && e[1].__element) kids.push([e[0], { type: e[1].__element, list: e[1].list }]);
     else props[e[0]] = __uiResPlain(e[1]);
   }
@@ -239,17 +239,17 @@ function __uiApplyRes(c, res) {
   // Ranges before values, items before selections.
   if (props.minvalue !== undefined) c.minvalue = __num(props.minvalue);
   if (props.maxvalue !== undefined) c.maxvalue = __num(props.maxvalue);
-  if (props.items instanceof Array && c.items) for (var n = 0; n < props.items.length; n++) c.add("item", props.items[n]);
+  if (props.items instanceof Array && c.items) for (const elem of props.items) c.add("item", elem);
   for (var k in props) {
     if (__uiResSkip[k]) continue;
     var v = props[k];
     if (__uiSizes[k] && v instanceof Array) v = __dim(v[0], v[1]);
     c[k] = v;
   }
-  for (var j = 0; j < pk.kids.length; j++) {
-    var child = __uiAddRes(c, pk.kids[j][1]);
-    child.__key = pk.kids[j][0];
-    c[pk.kids[j][0]] = child;
+  for (const elem of pk.kids) {
+    var child = __uiAddRes(c, elem[1]);
+    child.__key = elem[0];
+    c[elem[0]] = child;
   }
   return c;
 }
@@ -268,7 +268,7 @@ Window.alert = function (s) { alert(s); };
 Window.confirm = function (s) { return confirm(s); };
 Window.prompt = function (m, d) { return prompt(m, d); };
 Window.find = function (type, title) {
-  for (var i = 0; i < __uiWins.length; i++) if (__uiWins[i].text === title) return __uiWins[i];
+  for (const elem of __uiWins) if (elem.text === title) return elem;
   return null;
 };
 
@@ -335,7 +335,7 @@ function __uiColor(c) {
   return null;
 }
 function __uiFontSize(f, g) {
-  var x = f && f.size !== undefined ? Number(f.size) : g && g.font && g.font.size !== undefined ? Number(g.font.size) : 12;
+  var x = f?.size !== undefined ? Number(f.size) : g?.font && g.font.size !== undefined ? Number(g.font.size) : 12;
   return x > 0 ? x : 12;
 }
 
@@ -371,11 +371,11 @@ function __uiGraphics() {
       this.__push({ op: "fill", color: brush ? brush.color : null, path: (path || this.currentPath).slice() });
     },
     strokePath: function (pen, path) {
-      this.__push({ op: "stroke", color: pen ? pen.color : null, width: pen && pen.lineWidth !== undefined ? pen.lineWidth : 1, path: (path || this.currentPath).slice() });
+      this.__push({ op: "stroke", color: pen ? pen.color : null, width: pen?.lineWidth !== undefined ? pen.lineWidth : 1, path: (path || this.currentPath).slice() });
     },
     drawString: function (text, pen, x, y, font) {
       var f = font || this.font;
-      this.__push({ op: "text", text: String(text), color: pen ? pen.color : null, x: __num(x || 0), y: __num(y || 0), size: __uiFontSize(f, this), style: String(f && f.style !== undefined ? f.style : "") });
+      this.__push({ op: "text", text: String(text), color: pen ? pen.color : null, x: __num(x || 0), y: __num(y || 0), size: __uiFontSize(f, this), style: String(f?.style !== undefined ? f.style : "") });
     },
     drawOSControl: function () { this.__push({ op: "os" }); },
     drawImage: function (img, x, y, w, h) { this.__push({ op: "image", image: __uiImageJson(img), x: __num(x || 0), y: __num(y || 0), w: w === undefined ? 0 : __num(w), h: h === undefined ? 0 : __num(h) }); },
@@ -384,7 +384,7 @@ function __uiGraphics() {
       var size = __uiFontSize(font, this);
       var lines = String(s).split("\n");
       var cw = size * 0.58, w = 0;
-      for (var i = 0; i < lines.length; i++) w = Math.max(w, Math.ceil(lines[i].length * cw));
+      for (const elem of lines) w = Math.max(w, Math.ceil(elem.length * cw));
       var n = lines.length;
       if (boundaryWidth > 0 && w > boundaryWidth) {
         n = Math.ceil(w / boundaryWidth) + lines.length - 1;
@@ -405,14 +405,14 @@ function __uiRunDraws(win) {
   })(win);
   if (!drawn.length) return;
   __uiLayout(win);
-  for (var k = 0; k < drawn.length; k++) {
-    var c = drawn[k];
+  for (const elem of drawn) {
+    var c = elem;
     c.__draw = [];
     c.graphics.__rec = c.__draw;
     try {
       c.onDraw.call(c, { type: "draw", target: c });
     } catch (e) {
-      try { writeLn("onDraw: " + (e && e.message ? e.message : e)); } catch (e2) {}
+      try { writeLn("onDraw: " + (e?.message ? e.message : e)); } catch (e2) {}
     }
     c.graphics.__rec = null;
   }
@@ -498,7 +498,7 @@ function __uiProto() {
       var arg = t === "image" || t === "iconbutton" ? text : typeof text === "object" && text !== null && !(text instanceof Array) ? "" : text;
       __uiInit(c, t, this.window, this, bounds, arg, props);
       if ((t === "dropdownlist" || t === "listbox") && text instanceof Array) {
-        for (var i = 0; i < text.length; i++) c.add("item", text[i]);
+        for (const elem of text) c.add("item", elem);
         c.text = "";
       }
       if (t === "slider" || t === "scrollbar") {
@@ -521,7 +521,7 @@ function __uiProto() {
       if (t === "checkbox" || t === "radiobutton") c.value = false;
       if (t === "edittext" && c.properties.multiline) c.__multiline = true;
       if (t === "edittext" && c.properties.readonly) c.__readonly = true;
-      if (c.properties && c.properties.name) c.name = c.properties.name;
+      if (c.properties?.name) c.name = c.properties.name;
       this.children.push(c);
       if (t === "tab" && this.type === "tabbedpanel" && this.__sel.length === 0) this.__sel = [this.children.length - 1];
       return c;
@@ -608,21 +608,21 @@ function __uiProto() {
     removeEventListener: function (name, fn, capture) {
       var k = String(name).toLowerCase();
       var m = capture ? this.__capture : this.__listeners;
-      if (m && m[k]) m[k] = m[k].filter(function (f) { return f !== fn; });
+      if (m?.[k]) m[k] = m[k].filter(function (f) { return f !== fn; });
     },
     dispatchEvent: function (e) { this.__fire("on" + String(e.type || e).charAt(0).toUpperCase() + String(e.type || e).slice(1)); },
     __fire: function (name) {
       var r;
       if (typeof this[name] === "function") r = this[name].call(this);
       var l = this.__listeners[name.slice(2).toLowerCase()];
-      if (l) for (var i = 0; i < l.length; i++) l[i].call(this, { type: name.slice(2).toLowerCase(), target: this });
+      if (l) for (const elem of l) elem.call(this, { type: name.slice(2).toLowerCase(), target: this });
       return r;
     },
     __handlers: function () {
       var out = [];
       var names = ["onClick", "onChange", "onChanging", "onDoubleClick", "onClose", "onShow", "onActivate", "onDeactivate", "onResize", "onDraw"];
-      for (var i = 0; i < names.length; i++) {
-        var n = names[i];
+      for (const elem of names) {
+        var n = elem;
         if (typeof this[n] === "function" || (this.__listeners[n.slice(2).toLowerCase()] || []).length) out.push(n);
       }
       return out;
@@ -634,8 +634,8 @@ function __uiProto() {
 (function () {
   var all = ["Window", "Panel", "Group", "Button", "IconButton", "StaticText", "EditText", "Checkbox", "RadioButton", "Slider",
     "Scrollbar", "Progressbar", "DropDownList", "ListBox", "TabbedPanel", "Tab", "ScriptUIImage"];
-  for (var i = 0; i < all.length; i++) {
-    var C = __ecGlobal[all[i]];
+  for (const elem of all) {
+    var C = __ecGlobal[elem];
     var p = __uiProto();
     for (var k in p) C.prototype[k] = p[k];
     Object.defineProperty(C.prototype, "bounds", {
@@ -737,8 +737,8 @@ function __uiMouseListeners(c, type, capture) {
 // The mouse events that reach a listener at `c`: its own, and its containers' (`inherited`).
 function __uiMouseWanted(c, inherited) {
   var out = inherited.slice();
-  for (var i = 0; i < __uiMouseKinds.length; i++) {
-    var t = __uiMouseKinds[i];
+  for (const elem of __uiMouseKinds) {
+    var t = elem;
     if (out.indexOf(t) < 0 && (__uiMouseListeners(c, t, false).length || __uiMouseListeners(c, t, true).length)) out.push(t);
   }
   return out;
@@ -793,7 +793,7 @@ function __uiMouseFire(target, type, v) {
     var l = __uiMouseListeners(c, type, capture);
     e.currentTarget = c;
     e.eventPhase = phase;
-    for (var i = 0; i < l.length; i++) if (typeof l[i] === "function") l[i].call(c, e);
+    for (const elem of l) if (typeof elem === "function") elem.call(c, e);
   };
   var n = path.length - 1;
   for (var i = 0; i < n; i++) {
@@ -832,7 +832,7 @@ function __uiJson(c, inherited) {
     if (m) o.margins = m;
     if (typeof c.spacing === "number") o.spacing = c.spacing;
     var kids = c.children;
-    for (var i = 0; i < kids.length; i++) o.children.push(__uiJson(kids[i], mouse));
+    for (const elem of kids) o.children.push(__uiJson(elem, mouse));
   }
   if (c.alignment !== null && c.alignment !== undefined) o.alignment = __uiAlign(c.alignment);
   if (c.type === "checkbox" || c.type === "radiobutton") o.checked = !!c.value;
@@ -859,8 +859,8 @@ function __uiJson(c, inherited) {
 // The open windows of this script, for the host.
 function __uiSnapshot() {
   var out = [];
-  for (var i = 0; i < __uiWins.length; i++) {
-    var w = __uiWins[i];
+  for (const elem of __uiWins) {
+    var w = elem;
     if (w.__shown && !w.__closed) __uiRunDraws(w);
     out.push({ id: w.__wid, kind: w.__kind, title: String(w.text || ""), visible: !!w.__shown && !w.__closed, modal: !!w.__modal, root: __uiJson(w) });
   }
@@ -871,12 +871,12 @@ function __uiSnapshot() {
 
 function __uiOpenCount() {
   var n = 0;
-  for (var i = 0; i < __uiWins.length; i++) if (__uiWins[i].__shown && !__uiWins[i].__closed) n++;
+  for (const elem of __uiWins) if (elem.__shown && !elem.__closed) n++;
   return n;
 }
 
 function __uiWin(id) {
-  for (var i = 0; i < __uiWins.length; i++) if (__uiWins[i].__wid === id) return __uiWins[i];
+  for (const elem of __uiWins) if (elem.__wid === id) return elem;
   return null;
 }
 function __uiFind(c, id) {
@@ -914,7 +914,7 @@ function __uiDispatch(winId, id, kind, valueJson) {
   if (!c || c.enabled === false) return;
   var radio = function () {
     var sib = c.parent ? c.parent.children : [];
-    for (var i = 0; i < sib.length; i++) if (sib[i] !== c && sib[i].type === "radiobutton") sib[i].value = false;
+    for (const elem of sib) if (elem !== c && elem.type === "radiobutton") elem.value = false;
     c.value = true;
   };
   // A mouse click carries the pointer's details ({x, y, button, detail, …keys}).