CLI
Bitbucket Server v5.16.6
If I can get the issue to show up again I will. Maybe a few days though.
A bit of background into the scenario, assuming there are two PRs to the same project:
Under Pull Requests -> General we do have the following settings

But to my knowledge Renovate doesn't change the source branch when rebasing so I'm unsure why we are losing the approvals. Other information that maybe useful:
The ultimate question here is what config can I setup so that upon rebase, I don't lose approvals?
Transferring this to the main repo for discussion with @ViceIce and @iamstarkov.
I would expect approvals to be lost if you had the "Unapprove automatically on new changes" option checked. But as you mention, we're not changing the source branch. We do a "git force push" which does not change the source branch, but maybe BB server could have a bug that is triggered by it.
bb server removes approvals on all source code changes and a force push is a change for bb.
@ViceIce that seems to contradict this option, doesn't it?

ok, then it seems that force push is a source branch change.
a force push changes the source ref, so this is ideed a source branch change
So it sounds like the option is incorrectly labeled if so. It says "source branch" but it seems to be behaving as "source ref"
i think it is because a force push can change anything
Yes but the PR hasn't changed its target branch, no matter what we force push, so that's why I think their option is either (a) incorrectly described, or (b) buggy
Thanks to this conversation I was able to determine the set of google keywords to search and stumbled on a Jira ticket seemingly related to this
https://jira.atlassian.com/browse/BSERV-7673
I'll see if I can determine which version of the plugin we are using (will require me hunting down an admin) but I'm unsure the PR attached to the issue would prevent removals after a force push
OK, I'm going to close this issue then as it doesn't seem like we can do anything. Please update if/once you find out an answer to this, in case anyone in future stumbles on the issue too
Yes, it鈥檚 not related to renovate adapter