Re: menu-bar: disable items when no frame visible

[Richard M. Stallman]

    Because I configure my Emacs similarly to what Epoch used to do.  So when
    I start Emacs, I only get a one-line frame holding the minibuffer.

Would simply enabling recursive minibuffers give you what you want?

It occurs to me that in this kind of configuration, though you usually
see the minibuffer frame, the minibuffer is not active.  Do minibuffer
commands give you an error when you run them in the minibuffer frame
while the minibuffer is not active?

    Other cases of errors is when I use C-x C-f from a dedicated window/frame.

That is a completely different issue.  You won't get an error entering
the file name in the minibuffer.  You will get an error trying to
display a different buffer in that dedicated window.

For now, the solution is to use C-x 4 f or C-x 5 f.
After the release we could think about whether commands to
switch buffers should treat dedicated windows differently.