Assegnate 4 su 5 stelle

I love Custom Buttons, & they work very well, but it doesn't play very well with my Pale Moon Browser V27.3.0 64bit on Windows 10 64bit. Intermittently when a button initializes all buttons disappear, & the browser freezes, then needs to be forced to restart. When the latest version of Custom Buttons is installed 0.0.5.8.9.3 the red dot indicates the add-on is incompatible, same with previous versions????
►► https://i.imgsafe.org/91e646ba03.png
Isn't Custom Buttons Compatible with Pale Moon anymore?