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This version includes a new merge check to ensure that all submodules can be merged to the default branch in fast-forward mode. If we didn't merge the submodule before merging the main repository, we'd be able to do it afterward in fast-forward mode, and the link to the submodule will remain unchanged.
Please note that merge check only works for submodules hosted in Bitbucket it's been enabled in. Also, the validation is performed only at the first level of a submodule, and nested submodules will not be checked.
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