Hi, we have the same crash problem with Remmina under Wayland with both Ubuntu 17.10 and arch.
So I wrote a new test GTK app with crashes exactly with the following error.
mar 19 20:09:20 ub1710 kernel: prova1[2476]: segfault at 0 ip 00007f0c8dcc9dd6 sp 00007ffcd6197dd0 error 4 in libwayland-client.so.0.3.0[7f0c8dcc4000+c000]
Hoping this can help you to fix it, I developed a simple test&crash SNAP application here:
https://github.com/giox069/snapcrashbug
The only workaround I found is to disable wayland, as explained on my README.md
Thank you