Disable Overscroll History

Prevent horizontal scrolling from triggering forward / backward page navigation.

Since Chrome 80, horizontal overscroll navigation has - for now - become impossible to disable (due to the removal of the overscroll-history-navigation flag; see https://issuetracker.google.com/u/1/issues/172341945) This extension simply utilizes the `overscroll-behavior` CSS property to prevent overscroll navigation to help avoid frustration and accidental data loss. Notice: You will need to refresh tabs after install to apply behavior. Specific websites may also opt back in to navigation behavior by force-overriding `overscroll-behavior` (not likely but possible). The plugin may also not run on certain built-in browser pages, like chrome://settings, where you will still see overscroll navigation occur. The aim of this plugin is to override the default behavior for most websites to help avoid frustration and data loss where possible without excessive permissions. This plugin uses a single tiny CSS file.