Hello Tails Team and Testers,
The reason the screen resolution results in our recent tests of Tor Browser 9.5.4 through 10 didn't show as multiples of 50 is because we had the "Settings > Universal Access > Large Text" option enabled.
However, even with default text size the viewport and window size results don't show as multiples of 50.
We've communicated this and other issues to the Tor Project.
Best Regards,
Circletop
https://circletop.wordpress.com