Most Chrome extensions can easily be run in Firefox. Simply download the CRX and upload an copy to addons.mozilla.org as an unlisted extension and within a few hours the extension should be approved and ready to install in Firefox.

Firefox has strong support for the extension cookie management APIs: https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/cookies

Publisher is being discontinued soon and will be removed from Microsoft 365 installs