Do what you say and both work in the same branch. If the branch diverges from master and you need to catch synchronize and then one of you does a rebase the oth

Do what you say and both work in the same branch. If the branch diverges from master and you need to catch synchronize and then one of you does a rebase the other does git reset --hard origin/feature-branch. Alternatively just leave any cleanup till the end of the MR and designate one person to it