I know it may sound kind of obvious, but have you updated Firefox or checked out any versions of the extensions recently? Sometimes Firefox's updates have huge gaps between the extension(s), and if you don't stay up to date it can make them unusable.

I have the latest updates for FF as well as all extensions. It is a known issue for a long time and I was hoping it could be resolved one day... Thank you

There is an issue with 3 extensions: 1. Briskine. 2. Simple Gmail notes. 3. Boomerang. This issue is taking place only when Briskine is active and only on Firefox.

Issue with extensions means you need to contact the devs for the extensions.

Each one of these extensions are working fine with ANY other browser EXCEPT for Firefox.

Hi

I recommend that you provide feedback to the developers of those add-ons so that they can look into this further for you.

Each one of these extensions are working fine with ANY other browser EXCEPT for Firefox.

Extensions made for Chrome/Chromium based web browsers are not made the same and does not work in the (desktop) Firefox web browser nor the forks. Btw the vast majority of Extensions hosted on addons.mozilla.org are made by a third-party author(s) or company and not by Mozilla.