My colleague with a windows machine doesn't have this issue with the same code.
All my tests that pass normally when run in chrome - fail when run headless at the point where the user presses save and continue and another form displays on the same page.
The screenshot shows that the first form is filled out but does not show the second form as having appeared.
I've tried adding a fixed 5 second sleep to allow for any ajax or js (for investigative purposes) but the problem persists.
How can I figure out what the issue is given I don't get to see the browser itself with the issue, i just get the screenshot:
The save and continue button is highlighted but the new form hasn't rendered so the test fails.