I’ve duplicate the quark theme to have “mytheme” like explain in the documentation :
Theme Inheritance > Inheriting manually
I seems that’s I’ve succed but sometime is not working anymore in the top menu now.
When the mouse is on the menu page1, page2, page 3, I can’t reach the pages which are under page 1.
The menu (page 1 page 2 etc.) is disapearing when the mouse goes too low, and I can’t reach page 2, page 3 etc.