How do you troubleshoot merge conflicts flagged in a GitLab merge request?

GitLab flags an MR as having conflicts when the source and target branches have both changed the same lines (or GitLab can't auto-merge them cleanly) since the branch diverged. The MR page shows a "merge conflicts" warning and, for simple text conflicts, offers a "Resolve conflicts" button right in the browser.

1. Try the in-browser resolver - for straightforward conflicts, GitLab shows both versions side by side and lets you pick a side or edit the merged result directly, then commits the resolution to the source branch.
2. Fall back to the command line for complex conflicts - pull the latest target branch locally, merge or rebase it into the feature branch (git merge origin/main or git rebase origin/main), resolve conflict markers in your editor, and push the resolved branch back.
3. Re-run the pipeline - resolving conflicts doesn't guarantee the code still works together, so the MR's pipeline should re-run and pass before merging.
4. Re-request review if the resolution was non-trivial - if resolving the conflict meant making a real code decision (not just picking one side), it's worth a reviewer looking again rather than treating conflict resolution as purely mechanical.

The in-browser resolver only handles conflicts GitLab considers simple text conflicts; anything involving renamed files, binary files, or overlapping logic changes generally has to be resolved locally where you have full editor tooling and can actually run the code.