Cannot register merge from default branch to other
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### Problem to solve
When develop is your default branch there is missing buttons to create merge from this branch. Quite common we merge from develop to master and to do that you have to click a lot of things, because button is missing.
### Intended users
Merge request users :)
### Further details
Not needed, screen shows everything.
### Proposal
Just restore buttons:

### Permissions and Security
### Documentation
### What does success look like, and how can we measure that?
### Links / references
issue