Mentioned commit id is irrelevant though could be anywhere from 3.1.21

Is there any simple step to reproduce this?

It might be also useful if someone could try to identify all users who use this version of huggle (3.2.0) either by scanning the edit summaries or huggle3.css and then notify these users about this issue

To reproduce you can revert and warn anything, huggle obviously use next edit as dependency for rollback

The problem is caused by possible change in revert logic in mainwindow.cpp (I don't know which commit caused this though) it seems that now for some reason we jump to next edit right after call to Revert() and subsequent WarnUser call work with this->CurrentEdit, which in that moment points to next edit in queue (or nullptr in case there is no more).

I am working on a fix

This commit caused it https://github.com/huggle/huggle3-qt-lx/commit/ebecb24fa4bc8974a0b5c3cdfd5aa4d8cb8382ed

Thanks @Petrb.. If I had more time yesterday I would've tried to hunt the issue down properly.

it works to me: https://en.wikipedia.org/wiki/Special:Contributions/Petrb

I don't know how clean your repository is and I don't really know if sudo make install is working reliably, try to do a fresh clone, or just delete huggle_release folder, run configure script again and then execute huggle from release folder. You probably still run the old binary.

(ls -l which huggle will show you time from which this binary is)

Yeah, old version: -rwxr-xr-x 1 root root 3812720 Apr 3 00:12 /usr/local/bin/huggle