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merge-commit for this pull-request: can be excluded by Exclude Merge Commits option
history-modifying commits, created with fast-forward rebase or squash merge strategies: just don’t use these strategieswe recommend against using these merge strategies. Please contact support if experience any issues.
commits introduced by fork / sync / resolve-conflicts / upmerge workflows: rather rare case
You can use Pre-receive Hook and Merge Check independently, with a separate sets of settings. Or you may enable them both together, to combine validation of some rules as they are committed and postponing some checks until Pull Request merge.
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