The error isn’t on your side, the GitHub web editor simply can’t process the conflict. Resolving the conflicts locally is the reliable workaround.

Steps:

1. Pull the PR branch locally.
2. Merge or rebase the base branch into it (git merge or git rebase ).
3. Fix the conflicts in your editor.
4. Commit and push the updated branch.

If GitHub shows an error when trying to resolve conflicts, even though the servers are up, it usually means the web conflict editor can’t load the diff — the PR is too large, contains binary/minified files, or the PR index is stuck.

The simplest fix is to resolve the conflicts locally and push the result.
If that doesn’t work, the problem is on GitHub’s side and you’ll need to contact suppor

Try this :

Resolve the conflicts locally (most reliable):

git checkout
git fetch origin
git merge origin/main

or

git rebase origin/main

Fix conflicts in your editor, then:

git add .
git commit
git push --force-with-lease

Clear PR cache by pushing a no-op commit
Sometimes GitHub’s PR index gets stuck.
You can fix it with:

git commit --allow-empty -m "Trigger GitHub reindex"
git push

I hope this fix your problem

@Richard12434 If you find the merge markers annoying, I built a tool https://codeinput.com/products/merge-conflicts to visualize 3-way diffs. Give it a shot if you face another merge conflict.