The cursor works as intended, but gets stuck when DevTools is opened. The position coordinates are shown in the element in DevTools, but the location on-screen seems to stop updating in one or both axes.
Browser: Vivaldi (2.6.1566.49), Chrome
OS: macOS Mojave, Windows 10
Expected behaviour:

Actual behaviour:

It's not a terrible situation, because users aren't expected to open the Developer Tools anyway. Just a thing I noticed! :)