Editable part of MIDI-item cuts off before end of item

Reaper 5.30 Windows 10 x64 Project file: Problem: MIDI item ends before the item itself ends. It behaves as if it's a pooled MIDI item that has gotten stretched, except it's not pooled. If I drag it in the arrange view, the MIDI-editable part won't elongate itself to fill the entire item like it usually does. Instead I have to wiggle it around in the MIDI editor itself for it to work. I don't know how to reproduce this, but it has happened in the project file above. Maybe this is normal behavior? I can't say it has happened to me before.

Just like in other thread, this also happened to me many times, but also it was difficult to point out circumstance.

Did some tests with copied items . It's different, but might relate to this issue too. BTW. How d you get those comments with chords in?