So, I decided to turn this back on, after trying this extension called 'Night Mode Pro' and finding it worked flawlessly where others had failed me. Went to google calendar, and was instantly reminded why I disabled this one: 'an extension is causing the page to load slow' or whatever it says.

Edit: this guy in another review has the exact wording, so Im gonna steal his image link:
https://imgur.com/a/4bduYFx

60.9.0esr (32-bit) (the only one that works for my google phone).