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When clicking on the inactive version, you have the option to activate the inactive version. (This, in turn, makes the active one inactive.)
When the Activate button is clicked for an inactive engine version:
The active engine version becomes the inactive one.
If the engine is deployed for text translation, the deployed engine instance will be replaced.
If the engine is used for document translation, files from this point onward will be translated using the newly activated engine version.
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