It allows you to save a Google Slides presentation as a working html file using the browser's "complete webpage save" feature

When playing a Facebook video, this script stores the current time (minus ten seconds) so that when the page is refreshed (be-it after reopening the browser or manual refresh) or after it gets reset due to bad internet connection, the video resumes from where it stopped. Inspired by 'Youtube - Resume'

It turns wordreference.com dictionary into a single-page application, that is it doesn't reload the full page when navigating to a different word. It also minimizes distractions by hiding the left and right columns and by providing fullscreen mode.