I have been reviewing a number of HTML editors. The best was Dreamweaver when it comes to autocompletion. They did not get it quite right.
Here is how I think it should work.
When you type </ the editor should look to the left for the innermost nested unclosed tag, and autotype that, in lower case (unless you have upper case tags configured).
e.g.
<div> <span class="alien">Greetings!</span> </div>
If you type <div> it should not autocomplete right away the way CSE does now typing the full </div>. It should wait until you type </
If hit BS, that should inhibit that particular autotype.
For analysing problems, you should be able to point the cursor anywhere, and right click analyse. Then you see a summary display of the tag nesting, with missing tags shown in red, e.g.
<blockquote> <p> <span> (here) </span> </p> </blockquote>
You can click on any element in the analyse display to jump to the document where it is, or roughly should be. If you know precisely where a missing tag should go, it should be displayed in different colour, and that tag or all such tags should be autofixable.
You should then be able to insert the missing tag with a single keystroke.



