Cc: gerd.
moellmann@ gmail. com, alan@ idiocy. org, 77039@ debbugs. gnu. org Date: Sun, 23 Mar 2025 12:13:10 +0200
From: Eli Zaretskii <eliz@gnu. org> So in summary, I don't see anything abnormal here. If we want to keep the only-current-line-changed optimization in redisplay_internal, someone will have to come up with a smarter test for when line numbers are shown. I think the underlying problem is that when the line number of the current line becomes large enough to require more columns for line-number display, we must redraw the entire window to avoid the problem with shifting or line number described in https:/
/ debbugs. gnu. org/ cgi/ bugreport. cgi?bug=54091#5 . To clarify: this should not cause any flickering, AFAIU, because the comparison of glyphs in subroutines of update_frame is supposed to find that everything on the glass is already up-to-date and there's no need to draw anything. So flickering, which happens because portions of the window are actually redrawn on the glass, should not happen in this case.