I'm on Win 7, is there I way I can switch to ESR?
Or regardless of that, is it possible for me to get APCDM running on a non-ESR install? (since that would be preferable)
Regarding switching to ESR, I found out how to do so here: https://www.ghacks.net/2017/02/03/firefox-52-how-to-keep-on-plugins/
I'm thinking I could maybe switch to Pale Moon browser, assuming that they haven't disabled/blocked this stuff too (I hear that it doesn't)