Keep the minimap up for the whole pan

Starting a pan showed the minimap with the same 2.2 s fade-out timer as
a wheel step, so a longer pan lost the minimap halfway through.

While a pan is active the minimap is held like when the pointer is on
it, and the fade-out timer starts when the pan ends.

Author: MerkDesigns

CHANGELOG.md

@@ -50,6 +50,8 @@ Architecture v1 (`architecture-v1`), not yet released.
 
 ### Fixed
 
+- The minimap stays visible for as long as you pan the canvas, and fades out only after the pan
+  ends; it used to disappear two seconds into a longer pan.
 - Pressing a container's or text block's menu button again closes its menu instead of reopening it.
 - The JSON editor and workflow windows fade their glass in and out again; the glass stayed
   transparent for the whole fade and then appeared at once.

src/App.tsx

@@ -3115,6 +3115,17 @@ function App({ useDocument, useSettings, retained }: AppProps) {
     }
   };
 
+  // A pan keeps the minimap up for as long as it lasts, like pointing at it; the fade-out timer
+  // starts when the pan ends.
+  const panning = interactionSnapshot.activeInteraction?.kind === "pan";
+  const minimapHold = useStableCallbacks({ holdMinimap });
+  const wasPanning = useRef(false);
+  useEffect(() => {
+    if (panning === wasPanning.current) return;
+    wasPanning.current = panning;
+    minimapHold.holdMinimap(panning);
+  }, [minimapHold, panning]);
+
   const undo = () => {
     retained.runtime.callbacks.undo();
     rename.end();