New letterboxing defaults

I just noticed that Tor Browser is defaulting to using 998x699 as its screen resolution on my computer. Unless I'm crazy, I'm sure 1000x700 was the default letterboxing resolution on most screens - that's what it's been on this computer at least. Now the letterboxing works, but it is defaulting to these resolutions.

Tor Browser 10.0, Windows 10 64-bit,