An even more complete solution would be to swtich the computer off and go outside.
Facetiousness aside, disabling this feature is very secure but not very forward looking. The voice and video apis in the new web standards are an important part of providing proper, cross browser, cross device and multi os support for communication apps. That is what we should be aiming for.
The spec for this feature needs to be "disabled in all windows by default, can be explicitly enabled in a single window, that window cannot enable other windows". If Google just impelemented that I'm sure the "living standard" would follow....