WB 2.10 change "Pages Directory" blacked out

[Gast]

its only possible to change this directory name, if your page tree is empty: means: after a new install as one of the first steps

[avde]

I'm testing the new WB 2.10 and I noticed that I can not change/rename the pages directory under Admin/Settings/Show Advanced Options? How come? I used to change often.