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From version 2.0, Submodule Changes for Bitbucket will become a paid app. Once you update, your 30-day trial period will start.
Compatibility with Bitbucket
The app becomes compatible with Bitbucket Server and Data Center versions 6.0 and above. Talk
Roadmap
We're also happy to announce that we are going to add lots of new features to provide a high-level experience for teams that use PRs for working with submodules:
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