Big Screen should work fine with the default settings on Windows, however we do recommend a few things to make everything seamless.
Set a black wallpaper for main screen: Right click on Desktop > Personalise > Background > Solid Colour
Turn off screen saver: Right click on Desktop > Personalise > Lock screen > Screen saver settings > Screen Saver
Big Screen should work fine with the default settings on macOS, however we do recommend a few things to make everything seamless.
Ensure that Displays have seperate Spaces is checked. If this isn't checked then its not possible to extend to seperate screens: System Preferences > Mission Control > Displays have seperate Spaces
Set a black wallpaper for main screen: System Preferences > Desktop & Screen Saver > Solid Colours > Custom Colour
Disable screen saver: System Preferences > Desktop & Screen Saver > Screen Saver > Start After > Never
Turn on Reduce Motion to prevent screen sliding across when going fullscreen: System Preferences > Accessibility > Display > Reduce Motion
Automatically hide and show the menu bar to prevent it showing up on the main screen: System Preferences > General > Automatically hide and show the menu bar
To play YouTube videos with Firefox the Autoplay sound permissions needs to be set.
Click on information icon next to address bar. Change the value of Autoplay sound to Allow
Most browsers offer Tab/Site Muting which allows users to completely disable audio. This might be good for testing in some environments but we tend to find it can lead to issues and inconsistent behaviour. It can also be confusing when a site is muted without the operator being aware of it.