Blurred TT Instructor pixel preview in Big Sur

After upgrading to Big Sur, I’ve noticed the TrueType Instructor pixel preview became blurred. Besides that, Glyphs 2 preview is also incomplete.

Glyphs 2 (1346) on the left and Glyphs 3 (3050) on the right.

Big Sur changed some drawing routines. I filed a bug with Apple but I don’t have any responds, yet. I though I had worked around it. I’ll have another look.