[Suggestion] Flush command history to a "backup" file periodically

[Peter]

Currently, in the event bash or something below it crashes, that
session's command history is lost.
It would be nice if bash saved it somewhere periodically, it doesn't
have to be too often, let's say on every second command.
That way, history could be restored from the "backup" file when the
shell starts after a crash, for example.


Let me know what you think. Thank you.