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Submodule Diff Viewer add-on helps watch changes committed to a submodule in a standard Bitbucket Diff view as if they're committed to the original repository. It also gives an ability to watch Blame leave comments for more convenient pull requests review.
Submodule Diff Viewer also gives an ability to watch Blame, leave comments on the entire pull request, a particular file, or on specific lines of code in a file for more convenient pull requests review.
How to install and configure the app?
To install Submodule Diff Viewer, log into your Bitbucket Server as Administrator and install Submodule Diff Viewer directly from Atlassian marketplace or by file upload.
The app doesn't require any configuration. Once installed, you'll see the changes in the Diff tab for commits and pull requests with updates to a submodule.