I sent the same link to three Slack channels last Tuesday and realized I had zero way of knowing which one drove the 47 signups I saw that morning. Honestly, it was a bit of a panic - I had no idea if it was the channel for our internal team, the one for our beta testers, or the public channel where we share updates. I spent the next hour digging through our analytics dashboard, trying to piece together where those signups came from, but it was like trying to find a needle in a haystack. The Blind Spot in My Email Campaigns I was using full URLs in my email campaigns, thinking that it was the most transparent way to share links with our users. But the problem was, those links were often too long and ugly, and I suspected that they might be getting cut off in some email clients. I tried using a simple curl command to test how different email clients would handle these long URLs, but it didn't give me the insights I needed.…