Double free in WM/client.c

[D4yvid]

I'm running Debian 12 under Bedrock Linux, all packages are from Debian, and the entire NextSPACE project was compiled with debian tools, packages, etc. Restricted from any interference of other packages or distros.

Compiled on commit 0c08011:

I still cannot reproduce 100%, but when i triggered it, i closed a window using the Command + Q shortcut, so i'll send more info when i get it reproducible every time

[trunkmaster]

@D4yvid it's a kind of error that hard to catch. I've added extra check that could fix this error. Please report if you'll encounter this problem again.