Campaign Tracking Parameters overwritten by anything? anonymized?

Hi everyone,
I’m implementing campaign tracking parameters like mtm_campaign and so on into our newsletter links.
Looking into the campaign statistics in matomo cloud, I get campaign-names that seem to be overwritten: When my parameter is like
I can see loads of visits from my original campaign name, but I will also get visits from stuff like
most of those users come from the same ip located in the US and every matomo parameter is overwritten but the url parameters like ids for the shop and stuff are not.

Has anybody any idea of which mailclient or browser anonymizes tracking parameters within urls?