[masklinn]

Not just squash merges, rebase-merges also don't work.

> What tools are the best to do the equivalent but for squash-merged branches detections?

Hooking on remote branch deletion is what most people do, under the assumption that you tend to clean out the branches of your PRs after a while. But of course if you don't do that it doesn't work.

[Anamon]

> Not just squash merges, rebase-merges also don't work.

Are you sure? I almost exclusively rebase-merge, and I use ‘git branch --merged‘ all the time. It works perfectly fine for me.

Also conceptually it seems to make sense to me: you rebase your commits onto the tip of the target branch, so you can trivially follow the link from the tip of your source branch to the tip of your target branch, which as I understand it is what the command checks for.

[masklinn]

Sounds like you update the source after rebasing? Because if you rebase then push on the target git sees no more relation between the two than if you squash.