Re: BUG-000151050, "Using the Linear Burn mode layer blend downgrades the quality of the exported PDF layout," which will not and cannot be addressed, it would be a huge improvement for everyone if there were a warning that you're exporting to a format that doesn't support a blend mode you're using, kind of like when publishing a web layer. Despite originating this bug, I just ran into the issue again and it had been so long that I was scratching my head. Thankfully the paper trail of tech support cases was there to help but it may cause others countless hours of frustration to run into the error in Acrobat (as I did the first time!)
I'm not sure if it would be possible to have this warning even sooner (e.g. when the blend mode is chosen) given the program (or user) might not know what format the map will be eventually exported to, but that would be even better -- at least in my office, vector PDF is by far the most common. Thanks.
(This is the error received:)