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Greasemonkey/Tampermonkey/Violentmonkey test style

If you install this and all text turns red, then things are working.

Instali tiun ĉi skripton?
Author's suggested script

You may also like Autokahoot.

Instali tiun ĉi skripton
// ==UserScript==
// @name          Greasemonkey/Tampermonkey/Violentmonkey test style
// @namespace     http://userstyles.org
// @description	  If you install this and all text turns red, then things are working.
// @author        JasonBarnabe
// @homepage      http://greasyfork.org/scripts/1
// @run-at        document-start
// @version       20231121.2
// @include       *
// ==/UserScript==
(function() {
var css = "*{ color: #F00 !important; }";
if (typeof GM_addStyle != "undefined") {
	GM_addStyle(css);
} else if (typeof PRO_addStyle != "undefined") {
	PRO_addStyle(css);
} else if (typeof addStyle != "undefined") {
	addStyle(css);
} else {
	var node = document.createElement("style");
	node.type = "text/css";
	node.appendChild(document.createTextNode(css));
	var heads = document.getElementsByTagName("head");
	if (heads.length > 0) {
		heads[0].appendChild(node); 
	} else {
		// no head yet, stick it whereever
		document.documentElement.appendChild(node);
	}
}
})();