Frankly there is no feature for this so we make use of a bookmarklet

Step 1: Get The Bookmark

Click on Add bookmark place this code in url and use View Source in title then save

Code:
javascript:(function(){var w=window.open("about:blank"),d=w.document;d.write("<!DOCTYPE html><html><head><title>Loading Source</title></head><body></body></html>"),d.close();var f=d.createElement("form");f.setAttribute("method","post"),f.setAttribute("action","https://ole.michelsen.dk/viewsource/?uri="+encodeURIComponent(location.href));var i=d.createElement("input");i.setAttribute("type","hidden"),i.setAttribute("name","DOM"),i.setAttribute("value",encodeURIComponent(document.documentElement.innerHTML)),d.body.appendChild(f).appendChild(i),f.submit();})()


Step 2: Start Viewing

Simply open the site then click on view source in the bookmarks
#Happy Hosting