editor switch mode gone missing...

[vbplusme]

I think this isn't a big deal but more of an annoyance.

For some reason the "editor switch mode" has gone missing on my post editor. It the A/A function on the far right of the editor menu bar. I am pretty sure it enables switching between standard and advanced modes in the editor.

I have done quite a few things to try to figure this out including creating a new style, disabling plugins and resetting everything back to the defaults in vboptions but nothing works to restore this feature.

Any direction would be greatly appreciated toward helping me find the solution.