Comment 23 for bug 1912060

The MR with the second patch is still not merged upstream.
I tested on focal build without it (Fix subkey popmenu not showing after being dismissed) (https://launchpad.net/~fantonifabio/+archive/ubuntu/ubuntu-fixes) and the crash is not reproducible, so if you want you can at least apply the security fix and the build fix without the second patch with that additional fix is tested.
but without that additional fix you can select one of the characters of the sub-menu of the letter 'e' at most once then there is no longer the possibility of making it appear, and this does not seem good to me; in that case I would recommend making an additional sru with that other later (if you exclude it from the build security fix)