"Validating the marking of an essay question attempt." scenario fails on Windows FF, as the time to check "Save changes" takes long enough and window is closed before switching.

2 ways to solve this:

1. No extra step after saving changes, to ensure the switch window works.
2. Increase timeout for the preview window,

This was discussed in MDL-51322 and thuiner had concerns about the check after saving, to ensure we don't have any debugging on that page.

I tried with increasing the timeout (2nd option) but it still fails on win-ff, so going with 1st option to make this scenario pass on all platforms.