UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.133 Safari/537.36

Steps to reproduce the problem:
1. Plug in a gamepad and visit https://www.scirra.com/labs/gamepaddemo/ and verify the gamepad is recognised
2. Visit https://editor.construct.net
3. In the search field (under the Construct 3 logo), type "gamepad"
4. Double-click the "gamepad control" demo that is listed
5. Click the "Play" button in the toolbar at the top, and approve any popup window prompts
6. Try to use gamepad input in the popup window

What is the expected behavior?
Gamepad API to work.

What went wrong?
Gamepad API does not work. The demo remains on "no gamepad detected".

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 57.0.2987.133  Channel: stable
OS Version: 10.0
Flash Version: 

It appears the gamepad API only works if the full tabbed browser UI is showing. This breaks gamepad mode in Construct 3's game preview.

It actually works again if the page is in an iframe in a popup - if you click the "debug" button next to "preview" in Construct 3, it shows the game in an iframe and gamepad input works again. So actually it's only top-level frames in popup windows that don't work.

This may be related to bug 699199.