Color Picker is not hidden when setting its visibility to false #4789
Description
Step to reproduce using Aseprite with multiple window UI enabled:
- Pin the Color Picker (by pressing F4 for instance in a new sprite for instance).
- Click the home tab.
Current behavior:
The home tab is shown and the Color Picker remains visible on top.
Expected behavior:
The home tab is shown and the Color Picker is hidden. Once the user clicks back to the sprite's tab, the Color Picker should be displayed again.