Broken screenshots on Chrome when mobile emulation is on

Currently when running tests against a private test agent instance on Chrome with mobile emulation, the received screenshots are of a minimized browser window:

This behavior appears only when mobile emulation is enabled on Chrome browser.

[] latest wptdriver installed
] Windows 7 VM
[*] VM is restarted and no active RDP is done afterwards as per requirement

What is more interesting is that when I connect the VM via RDP, if I’m watching the test execution, the problem disappears.

The issue was somehow fixed - probably by an update to the test agents or a Chrome update.