Copying a piano-roll segment into a pattern copies it into the wrong pattern

System Information

NixOS 26.05

LMMS Version(s)

feec14c

Most Recent Working Version

No response

Bug Summary

Sometimes, when copying a piano-roll segment into a pattern, the segment is visually in the desired pattern, but the segment doesn't play when playing the pattern, and it instead plays in another pattern.

The issue #7108 is not the same as this one, but @michaelgregorius added a comment under it describing this same issue.

Expected Behaviour

I expected the piano-roll segment to play in the pattern that it shows up in.

Steps To Reproduce

The attached video shows how to reproduce the issue (make sure the video player isn't muted)

https://github.com/user-attachments/assets/56f5ece6-6655-4f21-b826-4c8adca4b951

Logs

Screenshots / Minimum Reproducible Project

No response

Please search the issue tracker for existing bug reports before submitting your own.

• I have searched all existing issues and confirmed that this is not a duplicate.

Start by watching the attached reproduction video and read the related comment on issue #7108 to understand the reported piano-roll and pattern behavior. Reproduce the bug in LMMS, then verify that a copied piano-roll segment plays in the pattern where it is displayed rather than in another pattern.