Your frustration is understandable, but if it makes you feel any better, IA does log most of their big fixes, so at least we know they're not idle when it comes to this sort of thing. Some how or another, this one simply has not yet topped the priority list: 2021 Change Logs 2022 Change Logs 2023 Change Logs
Steps to replicate are the most important thing anyone can give us. We've tried replicating this internally, and never had much luck. Obviously it affects some customers more than others, so finding out what's distinct about your environment/workflow would be very valuable.
We did fix some issues we found in a related area in 8.1.23; that may be why @pascal.fragnoud finds this less of a problem now, and I would agree with the suggestion to upgrade.
FWIW, I'm running test environments on three different systems, and I'm not seeing this on any of them. I'm presently testing on 8.1.26 in a windows 10 environment running on a PC and a windows 10 virtual machine environment that is running on a Mac.
I can reasonably consistently recreate it by opening 2 designers for the same project the first designer is always the broken one also almost always when i save changes on either one
Dude, you aren't on the latest version. Recreating it consistently on v8.1.17 is useless when it can't be recreated on the latest. Try the latest and report back. (IA won't be so blunt, but it's true all the same.)