Noteheads and beams are splitting into a standard staff linked to a Tab

GIT commit 523f66e / Windows 7

1) Guitar + Tablature template
2) Enter some notes in the standard staff

Result: the entered notes have a weird display: as mentioned in the title, noteheads and beams are splitted during the entering.
The layout reverts correct after input a new note, and so on.

- First example

- Second one

- Last one