The Gmail attachment icons userscript takes advantage of the previously-mentioned Stylish Firefox extension to add attachment icons to your Gmail account. In case you're not keen on what Stylish ...

It appears as though Google is testing some tweaked icons within Gmail on desktop to closely mimic icons seen on the Android and iOS apps.

To set this up, you need AutoNotification, a free app with some IAPs, which intercepts Gmail notifications and replaces them with identical notifications with one major difference: a third "Read ...