This is a really small issue and can easily be ignored - I just wanted to note it (and its easy workaround) in case a question about this ever comes up:

If you change the GUI scale from Blizz's interface, the widths of text fields/labels (or the font; can't really make it out) in the att interface (/att) don't adjust correctly, making the text go over two lines which in turn makes them overlap slightly with what's above and below it.
This issue fixes itself with a /reload

Below picture was taken after adjusting from 100% to 75%:

Blizzard changed the default text width in 9.1 which ATT has tried to work around, so it possible that any other addon may attempt to do its own 'fix' of text UI content and fail to properly adjust the allowed widths. Do you have any other addon which may be affecting fonts or other UI elements broadly?

I typically use 0.65 scale and ATT text does not wrap in the settings. I just checked now flipping between UI scale 0.65 and default and the ATT settings text remained the correct proportions without unnecessary wrapping.

I don't use any addons that tinker with the GUI, no. Just to be safe I've gone and recreated this with every addon except ATT disabled.

One additional detail I noticed: it only happens if I switch to 1.00 scale, reload, and then go back down to 0.8 or lower.

Also, apparently my resolution of 1366 x 768 is considered "small" nowadays, so that might be an additional factor.