The pic named "Cyberfox" is of my browser with a dark theme showing Colorful Tabs all transparent except for the active tab which is gray. All my browser extensions are also shown here.
The pic named "Cyberfox_themed" shows the browser with a different darkish theme, and Colorful Tabs is also transparent but for the gray active tab. All non-default themes cause Colorful Tabs to behave this way.
The pic named "Cyberfox_default" is right after I enabled the Default Theme. All the tabs are now properly colored and Colorful Tabs works perfectly, including custom tab colors for domains.
Question: how do I make Colorful Tabs work with a different theme from the Default Firefox Theme? I thought it was Classic Theme Restorer that was causing the problem with Colorful Tabs, but the tab colors work in Default theme (unless the Default theme disables Classic Theme Restorer, and that is why Colorful Tabs works with the Default theme?) Thanks for any help!