Correctly work with just added checkboxes:
fix previous workaround and use .getAttribute("checked") == "true" instead of "magic" delay
Force use customizable progress bar, if status bar is missing
Drop UI converter/updater and remove "uiVersion" preference:
* This is for 4 years old versions.
* Doesn't work correctly with Australis.
* Wrongly adds button at end of toolbar, if there is id of missing button after or separator/spacer.
Correct accesskey for "All settings…" menu item
(extensions.handyclicks.ui.showAllSettingsMenuitem = true)
Editor: autocomplete for "MutationObserver"