From time to time, entire blocks from different pages disappear. I can’t trace the trigger for this case. This is very important and dangerous because sometimes an entire page of blocks disappears - several hours of work.
Can you give me some advice, where can I read about such cases and how can they be avoided?
Welcome. Do you use sync? If so, have you checked the FAQ? e.g.:
Hello. I use dropbox sync.
Sync is well known of being problematic, including losing work, unless ensuring that:
When failing the above and losing work, try Dropbox recover.
Also in addition to what @mentaloid said, be weary of sync services running when you’re working in Logseq.
They will attempt to sync your files continuously and can cause issues and conflicts/data loss that way.
Whenever I forget to turn off my sync service Logseq will throw errors as the sync service locks files for syncing while Logseq is trying to write.
This is because Logseq will very frequently write to file, triggering the sync service to sync the file.
Do you not sync your notes at all or does it only happen once a day or something?
I turn sync back on when I’m done with Logseq. Though for that sync service it is only used as a backup on my PC, so I only have that issue if I happen to work on my PC. Which is not very often anyway. To sync across devices I use Git, because I like keeping things in my control 