Thanks for your suggestion, Matthias.
I found that the cause of the problem was not in hidden menu items but rather in a missing parameter in WB_Rockt on a call to show_menu2(). In index.php of WB_Rockt this call:
show_menu2(0, SM2_ROOT+1, SM2_CURR+1, '<li class=....');
must be changed to:
show_menu2(0, SM2_ROOT+1, SM2_CURR+1, SM2_TRIM, '<li class=....');
The SM2_TRIM parameter seems to solve the issue.
Why it worked in previous version and not in the current one is unclear to me but anyway WB_rockt doesn't comply with the show_menu2() documentation.
I have attached a version of the WB_Rockt index.php with the correction but I am not sure what the procedure is for having it included in the WB-Rockt download package.
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