Add feature to make a window opened on a desktop stay on that desktop after loading

[diogox]

Basically, this feature would fix the following problem:

• Open slow loading app (looking at you Slack)
• Switch desktop focus before it finishes loading
• App gets moved to the newly focused desktop when it finishes loading

Desired behavior: The app should stay in the desktop it was initialized in.

For more context, check out this Reddit thread where this was requested.

[diogox]

Check out this comment for a suggestion.