As I said, I wound up on Fennec F-Droid to get the unsupported extension; but if you have any recommendations on browsers on F-Droid that can streamline the process, I would certainly be interested in hearing about them!
It’s incredibly difficult to get the non-mobile-approved extensions added to Firefox. I remember it took me a couple of hours to get it configured and I had to change my browser to the nightly version, which I did not want to do for stability reasons.
It was even more difficult to install “unsupported” browser extensions. I had to install a very old version of Fennec F-Droid, install the extension, then update to the most current version of Fennec to keep the extension. Through trial and error across several different Firefox versions, I probably wasted 3 hours getting it set up on my phone.
If you are not motivated and tech savvy (ish), the chances of getting a non-supported extension on Firefox are quite slim.
Please, all I want is a microSD slot and a headphone jack. Who was asking for an Instagram camera lockscreen shortcut?