Menu Systems, comments

I'm learning JS little by little, but I had always considered it,
open-source until reviewing a few sites that offer menus: milonic.com,
codethat.com, smartmenus.org, jpowered.com, softcomplex.com,
deluxe-menu.com, etc.

These companies offer menus complete with licensing and pricing but I
am curious how they could enforce their licensing restrictions.
I must admit that they add value; I'm not yet good enough to code a
robust menu.

The best open-source (non-licensed) menu examples that I found were at:
mnsys.org
Even if you removed all the particulars for Opera, etc., I found the
coding a little complex.

I know there's arguments for / against menu's and they are convincing
on both sides.
I think they are partly a hold-over from C/S applications but they do
save screen space.

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