Also, if I implemented it this way, I would probably not use the software navigation wheel for navigating the code completion. I think it makes little sense to use these arrow keys if you can just directly tap on the entry.

Must be an app store bug. For me it says "Updated: Mar 10, 2012".

But what if you want to move the cursor up or down instead and just want to ignore code completion? In other editors, you do this by pressing the Esc key to dismiss the code completion list. I thought it would annoy people if this wasn't possible. 

Make sure you have an internet connection before you try to enable firebug. The easiest way to reset Firebug and enable it again is by refreshing the web view. You can do this by either re-confirming the url using the address bar or by simply closing and re-opening the preview screen. Then just tap on "Enable Firebug" again using the action button.

Btw, here is an older thread that discusses nearly the same:

If I find a way to have both I'll add it. It would probably be too technical and confusing to users who do not know the internals if I added it as an option.

That's an interesting alternative. The "save to camera roll" function is a good reason to do it that way - although I'd have to find a shorter button title...

Did you try the cursor navigation wheel by the way? 

I once implemented this and tried it out. Unfortunately, it interfered with vertical scrolling (if you disable auto line wrap) and zooming (two- and three-finger swipes were wrongly detected as pinch-to-zoom). So I didn't add this feature to a released version as a consequence.