When building the list of window PIDs, it's possible Mutter doesn't know
about the PID the client has and meta_window_get_pid() will return 0. We
should handle this case by not adding the PID to the list of PIDs
instead of adding an invalid one to it.
https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1184
{
MetaWindow *window = iter->data;
int pid = meta_window_get_pid (window);
+
+ if (pid < 1)
+ continue;
+
/* Note in the (by far) common case, app will only have one pid, so
* we'll hit the first element, so don't worry about O(N^2) here.
*/