Crash when extending melisma over rest

[miiizen]

Master/4.7 ONLY
Screencast_20251003_130201.webm

Crashes, enigmatically, when trying to _ past the rest. (But only on CI builds from GitHub; building it locally, it's fine.)

NB: the 4.6.1 port (#30269) does not crash.

Originally posted by @its-not-nice in #30228 (comment)

[cbjeukendrup]

Is it not by chance resolved by #30270?
(In any case, that should be merged asap)

[miiizen]

It appears to be fixed in master CI builds for me now!

[its-not-nice]

@cbjeukendrup @miiizen Can happily confirm (seems fixed now in nightly builds for Windows and Linux at least).

[cbjeukendrup]

I can confirm the cause was indeed the thing that was fixed by #30270