bug#16619: 24.3.50; REGRESSION: transparent *Completions* now

[Drew Adams <drew.adams@oracle.com>]

> What happens if you set frame-alpha-lower-limit to 100?

Yes, that fixes the problem.  Thank you, Daniel!  That gives
me a temporary workaround.

But I hope that is not the ultimate answer, and that you mean
that as something more than a workaround (I doubt that you do).
IOW, I don't think I should have to set this to 100.

I'm not familiar with this variable, but it seems to affect
all frames wrt frame parameter `alpha'.  I do not want to be
limited to not having frames of different opacity.  (No, I do
not currently use frames that are semi-transparent.  But I do
not want to be gratuitously prevented from doing so.)

> I don't think anyone made this change deliberately.

I don't suppose so either.  But I'm not sure what new features
that have been allowed might have been tweaked lately to make
them "work" better and which fix might have broken other things.
IOW, I have no idea what the cause is.  To me, this is just a
regression, regardless of the source.