For people who haven’t read the linked release notes: Mozilla is not dropping support for Windows 7-8.1 or macOS 10.12-10.14 at this time. Those users will be migrated to Firefox ESR (Extended Support Release, an LTS branch) that will receive monthly security fixes and some feature fixes for at least another 14 months.
Thanks, I did not realize that. I have one hackintosh still on 10.13.
I've actually been waiting for this release to switch to ESR. The regular release has been getting updates three or more times a month, each of which prompts daily nags to update, which gets tiresome across three or four computers with a lot of tabs open. I'm hoping for more like one per month on ESR.