User_script

User scripts, userscripts, or .user.js are scripts that make on-the-fly changes to specific web pages on the client side (in the browser or a proxy server), typically to change a sites appearance, or to add or modify functionality.

User scripts for Greasemonkey and Greasemonkey-compatible alternatives are written in JavaScript.

For tools other than Greasemonkey that apply user scripts to web sites, see [Cross-browser_userscripting] and Wikipedia.