Safari bookmarking does not always bookmark correct URL

[iStorm]

I've noticed Safari doesn't always bookmark the actual page/URL I'm on. For example, I'm tracking a UPS package and the URL looks something like this in Safari:
https://www.ups.com/track?track=yes&trackNums=1ZWA12345678901234&requester=ST/trackdetails

I tap the share button to 'Add Bookmark' or 'Add to Favorites'. I can already see the URL is different on the add bookmark screen:
https://www.ups.com/track?loc=en-us

...and sure enough, it goes to that page when I tap the saved bookmark. The tracking number isn't in the query string anymore, so obviously the tracking details aren't going to show up. My workaround whenever this happens is to copy the correct URL, edit the bookmark, and paste it in.

I'm running the latest version of iOS/iPadOS, but have had this issue for quite awhile now. Any ideas what could be causing this? Is anyone able to replicate this issue? Guessing it's a bug. Bookmarking seems to be working fine on the Mac.

Edit:
After playing with this some more, it seems to be the share button itself that's broken. Sharing to Messages, Mail, Notes, etc. also shares the shortened/dumb URL instead of the one that's shown in the address bar.

 

[DarkPremiumCho]

Fascinating. I was able to replicate this issue. The UPS URL was not the same when adding to bookmarks. You could see that short URL before tapping 'Save'.

I changed the UPS domain name to a random website, left the rest unchanged. When adding that one to bookmarks, the URL was not changed.

This made me think. The website owner decides that perhaps? I searched the short URL in the source code of that UPS page and found it's in the <link rel="canonical"> tag. Bingo.

Reference: why-does-safari-sometimes-bookmark-a-different-url