For the switch language function, the method CMSAbstractLanguageWebPart.GetCultures() is used to retrieve the URL, culture-code, and culture name. The URL will be used to the language switch button.
We found that when switch language, the user will get the link randomly appear with a senseless string as parameter (for example: https://example.com/Home?utm_source=aaa&utm_campaign=bbb&utm_term=5min&utm_content=Contextual&lang=en-CA).
Looks like that this URL is from our ad serving services, and somehow it is saved the URL to Cultures. But we can’t find any code and settings related to this. Thanks in advance.
Did the user come from a link which had all those UTM campaign parameters in it? If so, there's a good chance those parameters are "hidden" in the url structure somewhere and simply being displayed after the redirect happens.
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