I upgraded Firefox to 75.0 (on Ubuntu 18.04), and since I upgraded, Firefox resets the zoom level on most sites.
When I go to a new site I use CTRL++ to set the zoom level. For years Firefox has remembered this zoom level, so when I return to the site, it starts at that zoom level.
After upgrading zoom level changes back to 100% if I simply change tab. What is even more surprising is that it does not do that for all sites (reddit.com is affected, but unix.stackexchange.com is not).
How can I have the old behaviour back?