Browser window blackouts

If the browser window remains to blackout on entering the world, check the following:

Cause	How to Fix
Hardware Acceleration on the browser is disabled	Enable hardware acceleration via the browser settings
A gamepad is connected on the PC	Disconnect the gamepad connected to the PC
Build Error is unsolved	See Build Error for instructions

For example, if the browser is Chrome, enabling "Use hardware acceleration when available" via the "System" section on settings may fix the blackout.