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As you modify an element a further incremental version is automatically created. When viewing your requirement or test script, by clicking on the Versions tab you will be able to view all versions and compare the elements of a selected version to the current version.
At any stage you can decide to revert to a previous version of an element meaning that you can quickly reinstate an earlier version at any time. Note that when you revert to an earlier version a new version is created as the most recent version and all prior versions are retained including those created after the version you are reverting too. This provides a very powerful mechanism for controlling changes to your repository.
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