See the screenshot:
On the left side of the screenshot you can see AWB. On the right side of the screenshot you see Firefox on the same PC, open at Phabricator. It should be obvious to see that the font in the AWB window looks fuzzy and blurry in comparison to the Firefox window.
I am using Windows 10. From AWB About window:
Internet Explorer version: 11.0.17134.285
.NET version: 2.0.50727.8935
Windows version: 6.2
SVN 12255 (2018-09-15 13:57:07)
It's possible that this is related to T99546, but I'm not sure.