3.2

✨ Preference changes are now reflected immediately (#4).

Interacting with pref controls will have an immediate effect, without having to click a save button, which is therefore removed.
Instead, there is a new undo button, which reverts all the current changes to the state when the pref page was opened.
The undo and reset buttons are more intelligent: they are disabled when they would have no effect.

Demo: when changing the color in the color picker (at the right of the image) for the badge background color pref (in the middle), the toolbar button is immediately affected (at the left).