Created attachment 114509 [details] 1% transparency Subpixel font rendering is not present when the background has even 1% transparency and the background color is the same as 0%, resulting in a blurrier font.
Created attachment 114510 [details] 0% transparency
Alex, any ideas?
If Konsole renders to a separate QPixmap in the transparent case, then this is https://bugreports.qt.io/browse/QTBUG-22334.
(In reply to Nate Graham from comment #2) > Alex, any ideas? sorry, I don't know why this could be happening but I bet it's a Qt bug like Christoph said
*** Bug 410748 has been marked as a duplicate of this bug. ***
This is not a bug. Subpixel rendering relies on information about background pixels and consequently does not support transparency. Konsole (and freetype, Qt text renderer on Linux/BSD) does not have access to pixels under window. More info: https://devblogs.microsoft.com/oldnewthing/20150129-00/?p=44803
Created attachment 122359 [details] tilix Other terminals don't have this problem.
Created attachment 122597 [details] tilix: 50% black on white behind window Thanks for the example! It is still not perfect, but better than I thought/already saw before. Some kind of hybrid solution (using smooth transition from subpixel to normal when making background more transparent) might work. With Qt it is not possible AFAIK, but rendering engine might change.