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

[Drew Adams]

> I checked in a fix for this in revision#116242.
> 
> I'm afraid that I haven't understood the processing of frame
> parameters yet.  All I can do is fixing problems by trial and
> error.

Thanks for working on this, Martin.  Perhaps you do not
understand this stuff completely yet, but you no doubt still
understand it better than most of us.  And you keep working on
(hard) fixes.