Re: Extended menu items, when are :enable and :filter computed?

[Richard Stallman]

    I don't think this is considered as a feature (and I thought it was in
    the TODO list to change it so that submenus are only constructed when
    needed, but I can't seem to find it in the TODO file),

The reason for precomputing all the submenus is so that the toolkit
can display them all autonomously.  I think that's the only way some
toolkits can do it, so the idea of changing this is a non-starter.