I have a laptop with a touchscreen where GNOME 3.14 generally works well. Every
so often (after resumption from suspend? not sure) however, the gnome-shell and
all applications will lose all ability to detect any touchscreen interaction.
Restarting the gnome-shell (Alt+F2 -> r) does not fix anything. However, if I
log out and log back in the touchscreen interaction starts working again. In
fact, immediately upon log out I can use touchscreen interactions to select the
user in the gdm screen and so on. I would be happy to provide more information
if I knew where to look, and would be really grateful for any pointer.

Thanks.