I definitely feel for the author - the Chrome Extension team has been growing increasingly developer-hostile recently. My own open-source extension HabitLab ( https://habitlab.stanford.edu/ ) that I've been maintaining for the past 3 years is going to be removed in 2 days (got a 14-day removal notice for permissions even though all permissions it requests are used and needed, and every update I try to submit is rejec…
I'm really sorry to hear that--it looks like a useful extension and I'm sure you've put a lot of hard work into it. Naive question to you and to other extension developers here ... how does Firefox do when it comes to this issue? Is it just that the market share is so much lower that it's not worth developing for FF? I ask this as a happy FF user on mac, linux, ios.
The most painful incompatibility I've read about was in the Bitwarden extension, which basically doesn't support most operations in Firefox private windows because Firefox intentionally doesn't support getBackgroundPage() from there, and Bitwarden architected their extension to use that for all IPC between their frontend and backend layers. You can avoid that incompatibility by using runtime.sendMessage for that purpose, but they didn't know that at the time they wrote it (there's a warning about it in the MDN docs for getBackgroundPage now, but that warning wasn't there at the time). We happened to have gotten lucky in our extension in that we use sendMessage for the same purpose, but we certainly didn't know about that incompatibility at the time we were making the architectural decision.
Beyond just making it work, our team would also want to be able to automate regression tests against Firefox if we were to officially support it. For a long time, selenium was the most realistic option for that, but we switched away from selenium to puppeteer a year ago due to reliability issues with the former. Now that Firefox support in puppeteer is very recently starting to stabilize, we're hopeful we'd be able to use that, but we haven't tried it yet and it's new enough that we wouldn't expect it to be fully compatible/stable yet.