I have a custom version of the check-merge-conflict hook with three additional features:

• check binary files (based on extensions) in case of LFS merge conflicts
• ignore ======= pattern in .rst files, where it is valid syntax
• check for |||||||, which is a three-way merge conflict marker

I'd be interested in integrating them into prek, so they are faster, and other people can use them. Would this be valuable?