Reproduction steps:
1. Create a new project.
2. Go to Assets/Preference and enable "Verify saving assets".
3. Press collab button.
4. If saving assets window appears on the same screen, then move editor to another screen and redo step 3.
5. Press "Save All".

Expected result: Collab window will appear under its button.
Actual result: Collab window appears on the different screen.

Reproduced on: 2017.2.0b9, 2017.3.0a6.

Notes: There is no saving assets window when pressing collab button on 2017.1.0p5.