The default language in Glotio is the source language when all translations begin. This is important because Glotio understands that your website content started from that language in your platform.
IMPORTANT: I'd like to point out that changing the default language or any other language in your shop after doing some translation with Glotio, means that the tool will stop working/translating your texts until you set up again the default language such as at the beginning. Changing or deleting the default language doesn't allow to reactivation of the launch promo of the first language.
Take a look at this article: Error: Default language changed, Remote language deleted
You can see your default language and the languages already activated in your shop in the "My Languages" menu. Here you can see those that are already translated, those that are translatable and those that are being updated.
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