Pale Moon's Add-ons Support is changing. Again. Starting with Pale Moon 30.0.0 technological support for unmaintained Firefox Extensions will be restored. This will be accomplished by changing Pale Moon's internal application ID to the original Firefox identifier. Going forward, the ID that Pale Moon 25-29 used will no longer be valid.
For more information, please see the announcement on the Pale Moon forums.
What are Add-ons? Add-ons let you customize Pale Moon with extra functionality or a different look. There are several types of add-ons. Extensions expand the capabilities of the browser, themes allow you to personalize Pale Moon's visual aesthetic, and plugins further extend the browser with specialized external components such as the Adobe Flash Player.