The crash happened after I had cut off some 650 pages from a document with something like 700 pages. Then I wanted to refresh the TOC. The crash report number is https://crashreport.libreoffice.org/stats/crash_details/ac93d29f-a000-44e2-897c-6c3f4b2872c3 After I recovered from the bug, the reconstructed document had still 671 pages, so my deletion did not get through. Also the TOC was not updated.
Thank you for reporting the bug but it's of no use without more data. Please attach a sample document. The attachment will be public, remove any sensitive information before attaching it. See https://wiki.documentfoundation.org/QA/FAQ#How_can_I_eliminate_confidential_data_from_a_sample_document.3F for help on how to do so. When reporting a bug via https://bugs.documentfoundation.org/enter_bug.cgi an important question is if the bug is reproducible. So you need to confirm. If not, no point in keeping open. Further, another question is if you tried to reset user profile, you need to also test that. Please use the form to report bug. Crash report says you have version 7.2.0.0. See also similar bug 141388. I have set the bug's status to 'NEEDINFO'. Please change it back to 'UNCONFIRMED' once the requested document is provided.
Could be related to bug 139426, needs to be tested with master from https://dev-builds.libreoffice.org/daily/master/current.html
Timur, as told before, I recovered the document and continued to use it. Finally I succeeded to reduce the document to the smaller size but it is no longer the same one as it was in the moment of the crash and of course it was not ready to be publicly shown. - sorry.
Just thinking about what had happened with the particular file before the crash happened: I was installing Ubuntu from a live Stick Xubuntu 20.04.2 and I had started LibreOfficeWriter (probably version 6.4) from Xubuntu 20.04.2. I started from a very big file which had an associated style sheet. I did so in order to look up things in that document and to further use the stylesheet. After I had a lot of screenshots and notes from the Xubuntu installation steps, I stored the file on an USB stick. Later I reopened and edited it several times until I got problems when storing which I could not recover with LibreOffice from the live stick. Then I reopened the file on another computer with the mentioned development version. I could restore the file there. I continued editing it on the other computer. Finally tried to get rid of most parts of the old content with which I originally had started. Then .., see description above.
[Automated Action] NeedInfo-To-Unconfirmed
OK, let's close as ID. There must be reproducible steps.