Try this:
1. Start the preview. Don't close it.
2. Switch back to the editor window.
3. Press F12 in the editor window. Scroll to the end of the console log, make a screenshot.
.
By the way, why does your URL say "startTour"?
Maybe you are in the "construct tour" mode and that's why it doesn't work. Try to start the Construct normally from this link:
editor.construct.net