‘Show notifications’ defines whether you will receive order notifications while the Web Platform is running in your browser.
‘Show options’ manages Options visibility in the Instruments. Options are not included in the default view so you have to flip a switch to enable them. As soon as Instruments reload, Options will show up. It may take up to several minutes depending on your connection speed.
‘Dark Theme’ defines the colour scheme of the Web Platform.
The current platform version is also available in Settings. It is 3.37.0 in the screenshot above. You might need this information if you contact technical support regarding the Web Platform.