Collab button can only be used once - clicking it for the second time brings up a greyed-out window.

Steps to reproduce:
1) Create a new project.
2) Enable Collaborate via the Services tab.
3) Press the Collab button.
4) Make a change in the project (create an empty script for example).
5) Press the Collab button again.

A grey window pops up, instead of Collab options.

Reproduced on:
5.5.0b2 (96356e71f389), 5.5.0xb1, 5.4.0p1