When a frame is pasted into the timeline, the sprite editor is not invalidated

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Aseprite v1.2.16.2-x64, Windows 10.

To reproduce: Open a sprite with multiple frames. Select a single frame in the timeline, and copy it using Ctrl+C. Select a frame elsewhere in the timeline which is visually different to the first frame. Paste, either using Ctrl+V or using the menu item "Edit > Paste".

Expected behaviour: The sprite editor should immediately redraw itself to reflect the fact that the active frame has changed.

Observed behaviour: The sprite editor is not invalidated and redrawn. If the user takes an action which invalidates the sprite editor (such as scrolling it off-screen then back on-screen, or changing the zoom level), the displayed graphics will suddenly change.