To re-iterate and clarify the situation with extensions on Pale Moon 28, I'd like to announce the following:
With Mozilla having abandoned all XUL overlay, bootstrap and jetpack extensions, it is up to independent effort to keep this ecosystem alive.
While it is our intention to keep compatibility with (unaltered) Firefox extensions high, Pale Moon (now more so than ever) is considered a different application and as such needs application-specific extensions for it.
While the upcoming milestone release of Pale Moon 28 has lifted all restrictions in terms of version range and the further restriction on jetpack specifically for extensions that do not target Pale Moon specifically, they are not supported by us and there is no guarantee that they will work unaltered.
It is the position of the Pale Moon Project that unless the extension directly supports and targets Pale Moon, all Firefox extensions are considered to be unsupported and at the user's own risk. We will no longer impose any restriction upon them, nor any further effort be made to cater to them. What you see is what you get, and your mileage may vary. If a Firefox-targeting extension does not work or work fully on Pale Moon 28, it will have to be the extension that has to change to remedy that.
Any effort in the name of extensions on Pale Moon must continue forward as Pale Moon extensions via forking the Firefox extensions (license permitting) or bringing the developers across to our neck of the woods to target Pale Moon directly. In many cases, adjustments to extensions needed to target Pale Moon and making them Pale Moon extensions will be minimal, but a concerted effort must be made to specifically target the application.
This announcement is not a practical change from the current status quo, but a clarification and reminder of it.
As an extra reminder: Pale Moon's supported extension technologies are XUL based (either overlay, bootstrapped or using the deprecated jetpack libraries), and WebExtensions are not and will not be supported by Pale Moon in any way, shape or form.
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