Chrome does keep side loaded extensions through restarts. Firefox doesn't unless you submit to Mozilla for signing. But once signed you can install from a file or even your own site.
oh i actually have quite a few extensions that I made for my own use. i did make a small tab extension that I use every day that I did put in the app store for others. it's just a visual way to see what tabs you have open across all the windows and be able to switch to them or close them. super useful to my tab hoarding. links are in my bio
Does everything i wanted it to do and nothing more. I also made it because there were some hidden tabs sometimes that would play audio and I have a special section for tabs playing audio. I don't think that's as big a selling point anymore since autoplay can be disabled pretty reliably now but when I wrote it it was a big annoyance to me. In the end it's personal preference I guess. ~~link in bio if you want to try it out.~~
