That "underline" underneath taskbar icons was apparently added to indicate the application is open (vs. just pinned). I don't need this indicator.
Is there any way to remove the open application indicator that appears as a line underneath Windows 10 taskbar items?
I tried this custom theme, but it did not work. Other places where this has been asked:
Best Answer
update: This solution had some weird side-effects, so I stopped using it. Leaving for historical purposes (and people who don't want to shell out a few bucks for the new solution I use.)
I figured it out: NoLine custom theme + UltraUXThemePatcher!
Upvote/comment if you'd like the files required with detailed instructions. (You can mess up your computer if you don't install the correct theme that matches your version of Windows.)