Fix duplicate movie audio during scene transitions

frontend/src/player/screens.ts

@@ -8,7 +8,7 @@ import type { AudioSystem } from "./audio";
 import { isNativeAction } from "./musicroom";
 import { galleryClass } from "./gallery";
 import { parseExpression } from "./pyparse";
-import { movieDisplayable } from "./movie";
+import { disposeMovies, movieDisplayable } from "./movie";
 import { RenderHost, isDisplayableInstance } from "./render";
 import { Matrix4, blendMode } from "./rendertransform";
 import { strftime } from "./pymodules";
@@ -358,7 +358,10 @@ export class ScreenManager {
     inst.runners.forEach((r) => r.stop());
     inst.runners = [];
     inst.el.remove();
-    for (const id of [...this.movies.keys()]) if (id.startsWith(`${inst.name}|`)) this.movies.delete(id);
+    for (const [id, element] of [...this.movies]) if (id.startsWith(`${inst.name}|`)) {
+      disposeMovies(element);
+      this.movies.delete(id);
+    }
     if (forget) this.shown.delete(inst.name);
   }
 
@@ -462,13 +465,13 @@ export class ScreenManager {
       this.nodes(inst.def.body, ctx, children);
       inst.el.replaceChildren(...children);
     });
-    // a video taken out of the page pauses by itself; carry on, and forget the ones no screen shows now
+    // Preserve cached players on redraw; explicitly stop those no screen shows.
     for (const [id, element] of [...this.movies]) {
       if (this.moviesSeen.has(id)) {
         const video = element instanceof HTMLVideoElement ? element : element.querySelector("video");
         if (video && video.paused && !video.ended) void video.play().catch(() => {});
       } else if (id.startsWith(`${inst.name}|`)) {
-        if (element instanceof HTMLVideoElement) element.pause();
+        disposeMovies(element);
         this.movies.delete(id);
       }
     }