Carla VST GUI doesn't display properly

[DanielBielak]

macOS 10.14.6
Carla version 2.5.9 (and earlier)

Loading the Carla VST in a DAW (Renoise) results in the Carla VST GUI being merely a small window titled, "falkTX: Carla-VstShell," and containing only the text, "No parameters available." and a button labeled, "Random."

However, I think that the first time I ever loaded the Carla VST, the Carla VST GUI displayed properly.

I think this issue might be related to issue #1956.