From the strace file, I need to assume you installed LibreOffice from TDF (libreoffice.org) because it uses /opt
directory. Please try the following on the command line:
/opt/libreoffice7.0/program/soffice --safe-mode
(if you have installed 7.0.4.2 now) or
/opt/libreoffice6.4/program/soffice --safe-mode
(if you have installed 6.4.7.2. now)
Does this work?
**Please also note** If a problem is caused by a corrupt user profile, reinstalling LibreOffice won't help at all, since this won't touch the user profile. Therefore: Before reinstalling check whether the user profile might be the cause of a problem.
- Start LibreOffice
- Restart in Safe Mode using
Help → Restart in Safe Mode
and confirm the restart using button: Restart
- Click button
Continue in Safe Mode
- Perform the procedure showing the problem and check whether the problem is gone (If you need to open a file, use
File → Open
- do not use some other procedure)