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TrujilloR → created an issue.
I noticed the issue with saving after updating the module. Problem is, on the file ILangTranslatorUi.php it tries to fetch the providers with this:
$providers = $ilanglTranslator->getState('providers');
Then if the provider you are trying to save is not there, it tries to save it. The problem is, for saving the provider, it makes sure the provider is not already in that providers array, but $providers returns undefined when empty so the function crashes and the provider never gets saved in the state since the function crashes before. I made a small validation and seems to solve the saving issue.