setViewportSize broken?

[bminsky]

Starting around March 6, setViewportSize stopped changing the resolution. We run private instances, but I've tested on your site and see the same issue.

Here are the results:
https://www.webpagetest.org/result/170310_QW_11VK/
Here's the script:
setViewportSize 375 667
navigate http://whatismyscreenresolution.net/

Searching has turned up similar issues. The solution was to put a tab between the height and width but I don't believe that's the current issue. The script text field doesn't seem to take tabs, and when I click the yellow 'script' above the "Re-run the test" button it seem to have automatically added the tab.