CSS/HTML layout debugger

css-layout-hack.js

// create a bookmark and use this code as the URL, you can now toggle the css on/off
// thanks+credit: https://dev.to/gajus/my-favorite-css-hack-32g3
javascript: (function() {
	var styleEl = document.getElementById('css-layout-hack');
	if (styleEl) {
		styleEl.remove();
		return;
	}
	styleEl = document.createElement('style');
	styleEl.id = 'css-layout-hack';
	styleEl.innerHTML = 'html * { background: rgba(255, 0, 0, .1); box-shadow: 0 0 0 1px red; }';
	document.body.append(styleEl);
})();