(Former Mozilla developer here, who worked on GeckoView[1], the modern way to embed Gecko into Android apps, including all currently shipped Mozilla browsers on Android)
From an engineering perspective, the sad thing about this is that the work to finish extensions in GeckoView was essentially completed in the months after the initial Fenix release.
When GeckoView was still being rolled out into release, we understandably wanted to restrict the selection of addons only to those that exercised APIs that we knew were ready for production. Since that time, however, the WebExtensions work was essentially completed -- since that time it has entirely been a business decision to continue restricting the selection of addons available.
I didn't personally work on the WebExtensions bits, but I know that those who did were frustrated that their work to finish fleshing out full extension support was being held back for seemingly arbitrary reasons (that were never explained to engineering).
[1] https://geckoview.dev
From an engineering perspective, the sad thing about this is that the work to finish extensions in GeckoView was essentially completed in the months after the initial Fenix release.
When GeckoView was still being rolled out into release, we understandably wanted to restrict the selection of addons only to those that exercised APIs that we knew were ready for production. Since that time, however, the WebExtensions work was essentially completed -- since that time it has entirely been a business decision to continue restricting the selection of addons available.
I didn't personally work on the WebExtensions bits, but I know that those who did were frustrated that their work to finish fleshing out full extension support was being held back for seemingly arbitrary reasons (that were never explained to engineering).
[1] https://geckoview.dev