Provide a label attribute for toolbar buttons
requested to merge henry/tor-browser:add-label-to-toolbar-buttons-bug-41283 into tor-browser-102.2.0esr-12.0-3
Also tidy up the code to ensure the buttons are fully initialized whether they are part of the DOM on load, or if they are added later through customization.
Closes #41283 (closed)
Closes #41287 (closed)
Edited by henry