Modify an option in "advanced style properties" changes the type of a tab staff

Nightly, August 21 (aa7af8d) / Windows7

I found the explanation to my question this morning in the comment #3 of this issue: http://musescore.org/fr/node/30231

I have yet not had time to look when the problem occurred.

So:

1) New score for Electric Guitar: Tab staff 6.str common-> Next (32 Measures, 4/4) -> Finish

2) Click-right -> Staff Properties -> Advanced style properties

3) Fret Marks: tick on letters, or above lines, or continuous lines -> ok -> ok

4) "I"

Result: Surprise! "I" dialog. display a treble clef8vb and a standard staff!

- The result will be the same if, in "Advanced style properties", you change something in Notes values ​​(symbols, show Rests... ) I have not tested everything! (:

- Same result if initially you start by choosing a Simple tab staff or a Full tab staff.