Tampermonkey is a popular userscript manager and browser extension that helps you customize the way websites look and function. It allows you to write and install user scripts that make on-the-fly changes to web page content after it has been loaded in the browser. Tampermonkey also provides a set of useful APIs and a dashboard for managing installed user scripts. The app also allows you to manage, edit, and debug user scripts, and it supports all major browsers including Chrome, Firefox, Safari, and Edge. With Tampermonkey, users can easily enhance, customize, and change the way websites work to meet their individual needs.
It does not do JavaScript, which is 99% of the reason for Tampermonkey.
does not do anything that makes it tampermonkey
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Change of style, not of user scripts!