Cannot create merge requests for newly created branches.

Recently updated from CC (8.7.5) to EE 8.12.7 (ubuntu).

Newly create branches don't show up with a "merge request" button. I've verified this on several users.

This problem looks an awful lot like this:

Which should(?) have been fixed in our version.

see screenshot -- user has "owner" privs on the project.

Cannot create merge requests for newly created branches.

Push a change to a NEW branch. Look for it in the "merge requests" window -- note that it's not there. See screenshot,

It should have a merge request button.

No merge request button.

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(For installations with omnibus-gitlab package run and paste the output of: sudo gitlab-rake gitlab:check SANITIZE=true)

(For installations from source run and paste the output of: sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)

(we will only investigate if the tests are passing)

(For installations with omnibus-gitlab package run and paste the output of: sudo gitlab-rake gitlab:env:info)

(For installations from source run and paste the output of: sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production)

(If you can, link to the line of code that might be responsible for the problem)