For a few years now I observe a strange behaviour, most likely triggered by enduser's email clients using my webapp (Ruby on Rails system, doesn't matter tho).
I am running a mid sized business and send out thousands of mails to my customers each month who buy leads from me.
The emails include two links, one to buy the lead and the other to give feedback. There is a dynamic part in both URLs which is a UUID, example:
offer/968ec0c1-e105-4c70-95b2-fd0c799b58f3
and
feedback/968ec0c1-e105-4c70-95b2-fd0c799b58f3
Every now and then, my webapp gets accessed at the same time on both links (which makes me confident it is not the user since it is the very same second they get accessed) but with different dynamic parts in the url, so i see in my logs
offer/NGVjZjA0YT
and
feedback/NGVjZjA0YT
It is always a random string with a length of 10 chars.
So this is not a big deal since it happens only 1-2 times per week and as far as I can tell no user is really affected by this, but still I wonder what's behind this. Did any of you experience a similar thing?
Maybe an email client wants to crawl / load a preview, seeing an uuid pattern in the url and changes it because whatever?!
I disabled link click tracking in the email sending provider (sendgrid), just as a side note. So they won't / shouldn't replace the email links. Also experienced this when sending links via AWS SES.
Im just curious. Any ideas or experiences? Thanks in advance & have a great day!