PSA: Gmail has potentially broken 1-click-unsubscribe

I operate a tiny service that sends ~100 emails everyday, mostly to friends and family. This service uses SendGrid to send the emails. A few months ago, I noticed that almost all my users had unsubscribed. Including myself, even though I had not done so! I reached out to SendGrid for an explanation, and just received one. This sounds like a problem that will impact a large number of other SendGrid users as well. > Thank you for reaching out to Twilio SendGrid Support. My name is _____ and it would be my pleasure to help you. Apologies for our delay in getting to your ticket, we are experiencing a larger volume of support requests recently and are working through them as quickly as we can. > My apologies for the inconvenience this has caused. This is a part of a known issue that we are experiencing right now. What is happening is google recently made a change where it clicks each link and has been triggering the unsubscribe. Our engineers have been notified and the issue is being reviewed by our teams in order to produce a quick and effective resolution. > Currently, our team has a script removing these automatic unsubscribes caused by this change so you dont need to make any changes or take action. You may notice click and open statistics being inflated. At the moment we do not have a way to filter out the inflated clicks and opens from your analytics but are working on mitigating this going forward. If you are using our webhook you can filter out the inflated clicks and opens by excluding any useragent titled “Gmail-content-sampling”.