With all due respect: I don't have time. I just asked because this was an issue last time I tried sway, and I was curious about improvements since then. It was not meant to razz on your wm :)
As a maintainer and contributor to several projects I already use (and thus see the return on) I already see myself too short on resources to follow up everything I'd like to.
Trying to fix shortcomings in projects which (for me) are not yet production ready just doesn't make it onto my TODO list. I hope someone does help you fix this though.
Really. No harm meant. Hope it didn't come off that way.
That's fine, sticking with X is a totally acceptable option. If they _want_ to move to Wayland, though, and it's missing something they need, then of course they should help work on that thing.
Given that these issues has persisted for so long and that they seem solved in Gnome and KDE...
Not accusing you of full NIH, but are there any technical reasons for not just reusing/leveraging kwin or whatever Gnome uses, instead of creating your own compositor library where all these issues has to be solved, yet again?
kwin and Gnome's solutions aren't reusable on other compositors. Gnome is awful at making their stuff reusable. KDE is much better, but their clipboard stuff isn't reusable, and Sway's likely won't be either due to the nature of the problem. There are plans to collaborate more with KDE on reusing KDE components in Sway and other compositors, which both parties are excited about.
I've been using Wayland on Fedora 25 GNOME sessions for a few weeks now. I've not noticed any hiccups on copy/paste and I've definitely been doing it across Wayland-native and XWayland applications.
Sway works great as long as you have a system that can handle Wayland. I've been having terrible luck with NVidia hardware lately -- proprietary drivers are known not to support Wayland, and Wayland / Nouveau has been unstable with the hardware I use. But AMD and Intel systems are rock solid, and I've switched over to sway there.
http://swaywm.org/