vlo Gate None

vlo Gate None is a valve on a wire. Connect anything to its value input - a model, a latent, an image, a string - and it passes it straight through unchanged. Flip disabled to true and it outputs None instead. That's the whole node, and for a lot of ComfyUI plumbing that's exactly what you want.

Why would you bother? Because a gate is a bypass you can toggle from inside the data, rather than by right-clicking and muting a node. ComfyUI's optional inputs read an unconnected or None value as "skip me," which is the engine fact that all the switch-and-fallback plumbing is built on. So the pattern is: gate a branch, and when you don't want it, set disabled and the branch goes quiet without you touching a single wire. vlo's own default workflows use this to switch features in and out between runs - it's the kind of node that never gets a blog post and quietly saves you ten minutes a day.

Inputs and output

• value - any type. The socket is a MatchType from ComfyUI's newer V3 authoring API, which is just a properly typed way of saying "any of these." A model will fit, a mask will fit.
• disabled (boolean, default false) - the gate. When true, the output is None.
• value (output) - your input, or None.

That's the full inventory. Two inputs, one output.

The one thing to watch

None is a real value, not a magic "also run anyway" signal. Anything downstream that requires the value - a node whose input isn't optional - will throw when it gets None. Gate into optional inputs, or chain a fallback after it, and it behaves beautifully. Try to gate the only input to a mandatory socket and you'll learn what "got a None" errors look like.

Install

It's part of the ComfyUI-vlo pack (the companion node set for the vlo video editor), so it arrives with all the other vlo nodes:

cd ComfyUI/custom_nodes
git clone https://github.com/PxTicks/ComfyUI-vlo.git

Restart ComfyUI and it'll be under utils/logic. No extra dependencies, no models, no API keys - it's a three-line function with a toggle, which is the whole point.