Where is my sidechain chooser?

9

In Noise Gate example there is also such comment above return:

// the sidechain can take any layout, the main bus needs to be the same on the input and output

return (layouts.getMainInputChannelSet() == layouts.getMainOutputChannelSet() &&
(! layouts.getMainInputChannelSet().isDisabled())
);

Maybe it would explain something, but I am not sure what