Starting Firefox under a Wayland compositor (sway, in my case) with ''MOZ_ENABLE_WAYLAND=1'' and copying some multi-line text results in newlines of the form '''\r\n''', i.e. Windows-style, instead of the expected '''\n'''. Starting Firefox with the X11 backed, i.e. without ''MOZ_ENABLE_WAYLAND=1'', doesn't exhibit the issue. This is most certainly a bug since Wayland is a Unix-like protocol, and as such newlines should be of the form '''\n'''. However I am finding the bug tracker a little daunting and I am not sure how to check whether it is already known or not.