If you insist on knowing, include a different url in both that goes to the same place and use your damn server logs. You don’t need google analytics and whatever.

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vel0city 5 hours ago | parent [-]

Isn't putting in a different query string "including a different url that goes to the same place"?

Isn't this functionally the exact same?

	▲	zaphar 4 hours ago \| parent [-]
		presumably you control the urls you are sending in the email. As a result if you want to use query strings that's fine. The issue only arises when you use query strings to implement tracking on someone else's site instead.