When using a mobile device and after clicking on a feature, the popup does not always appear in the correct location. Sometimes the popup appears off-screen and the user needs to pan the map in order to see it. Rotating the mobile device and then rotating it back to its original position seems to make the popups appear in the correct locations.
Devices where this behavior has been observed
Nexus 5
HTC One
Note that this does not seem to be reproducible on the desktop, even when emulating a mobile device in Chrome.
When using a mobile device and after clicking on a feature, the popup does not always appear in the correct location. Sometimes the popup appears off-screen and the user needs to pan the map in order to see it. Rotating the mobile device and then rotating it back to its original position seems to make the popups appear in the correct locations.
Devices where this behavior has been observed
Note that this does not seem to be reproducible on the desktop, even when emulating a mobile device in Chrome.