unfix position

dft-position-unfixed.js

// ==UserScript==
// @id             dft-postion-unfixed
// @name           Remove position fixed
// @version        1.0
// @namespace      dft
// @author         Matthew Goodall
// @description    Changes position:fixed to position:relative
// @include        *
// @run-at         document-idle
// ==/UserScript==

function replace(old, _new) {
    var parent = old.parentNode;
    parent.insertBefore(old, _new);
    parent.removeChild(old);
    return _new;
}

function cleanStyleSheet(sheet){
	if (!sheet.href || sheet.href.split('/')[2] === window.location.hostname){
		// Same origin stylesheets can be modified
		var rules = sheet.cssRules;

		if (!rules){
			return;
		}

		for (var r = 0; r < rules.length; r++){
			var rule = rules[r];
			console.log(rule);
			if (rule.style && rule.style.position === 'fixed'){
				rules[r].style.position = 'relative';
			}
		}
	} else {
		// The stylesheet needs to be retrieved and put into the document directly
		GM_xmlhttpRequest({
			method:'GET',
			url:sheet.href,
			onload:function(resp){
				// place the stylesheet at the end of the document
				// don't need to delete the existing one since this will be applied over it
				createStyleSheet(resp.responseText);
				// and finally clean it
				cleanStyleSheet(document.styleSheets[document.styleSheets.length - 1]);
			}
		});
	}
}

function createStyleSheet(content){
	var sheet = document.createElement('style');
	sheet.setAttribute('type','text/css');
	sheet.textContent=content;
	return document.documentElement.appendChild(sheet);
}

// START
var sheets = document.styleSheets;
for (var s = 0; s < sheets.length; s++){
	var sheet = sheets[s];

	console.log(sheet);

	if (sheet){
		cleanStyleSheet(sheet);
	}
}