Makeshift Theme Switch

Very simple temporary theme switcher for any page

K instalaci tototo skriptu si budete muset nainstalovat rozšíření jako Tampermonkey, Greasemonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Userscripts.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat manažer uživatelských skriptů.

(Už mám manažer uživatelských skriptů, nechte mě ho nainstalovat!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(Už mám manažer uživatelských stylů, nechte mě ho nainstalovat!)

// ==UserScript==
// @name         Makeshift Theme Switch
// @namespace    https://mkps.app/
// @version      1.0.4
// @description  Very simple temporary theme switcher for any page
// @tag          utilities
// @author       MK
// @license      MIT
// @match        *://*/*
// @icon         data:image/png;base64,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
// @grant        GM_addStyle
// @grant        GM_registerMenuCommand
// ==/UserScript==

(() => {
	"use strict";

	const SESSION_STORAGE_KEY = "MK_userscript_makeshiftThemeSwitch_status";

	const STYLE = `
		html, img, canvas, embed, video, object, iframe {
			filter: invert(1) hue-rotate(180deg);
		}
	`;

	let styleElement = null;

	function main() {
		setState(getStoredIsOn());
		GM_registerMenuCommand("Switch theme", switchTheme);
	}

	function switchTheme() {
		setState(styleElement == null);
	}

	function setState(on) {
		if (styleElement) {
			if (!on) {
				styleElement.remove();
				styleElement = null;
				setStoredIsOn(false);
			}
		} else if (on) {
			styleElement = GM_addStyle(STYLE);
			setStoredIsOn(true);
		}
	}

	function getStoredIsOn() {
		return sessionStorage.getItem(SESSION_STORAGE_KEY) == "true";
	}

	function setStoredIsOn(value) {
		sessionStorage.setItem(SESSION_STORAGE_KEY, value);
	}

	main();
})();