From: JD Smith <jdtsmith@gmail.com>
Date: Tue, 5 Dec 2023 18:06:41 -0500
Cc: 67604@debbugs.gnu.org
Before or after the test?
After the test.
OK, so this was likely a false positive then. I’m out of ideas. Maybe Windows is magically immune.
Unlikely. More likely is that we need some specific metrics of the
displayed stuff to see the problem (which is therefore very rare).
For me both NS and Mac builds with your most recent xdisp.c fixes exhibit the same motion issue. Do you have anyone you can call in to try the simple test on another build?
Not really, no. But reproducing the problem is just a step towards
debugging it, so the alternative is for you to step through next-line
and its subroutines