ComfyUI-DynamicInputsHotFix

Workarounds for dynamic input rendering bugs in ComfyUI's Vue frontend.

What Are Dynamic Inputs?

Dynamic inputs allow a node to spawn unlimited input sockets on-the-fly as you connect wires to it. Instead of having a fixed number of inputs, the node automatically creates new slots when you connect something, and removes them when you disconnect. This is useful for nodes that need to accept a variable number of inputs (like merge nodes, concat nodes, etc.).

The technique uses the * (asterisk) type to accept any connection, then inherits the actual type from whatever gets connected. Credit to cozy_ex_dynamic for the original implementation pattern.

The Problem

Since the Vue nodes merge (~September 2025), custom nodes using dynamic inputs (this.addInput() in JavaScript) have visual bugs:

1. New slots don't render until page refresh
2. Slot colors don't update when type changes on connect
3. Slot colors stay stale after disconnect (unfixable from extension)

This affects any node using addInput()/removeInput() in onConnectionsChange, including cozy_ex_dynamic and similar.

What This Provides

• Example node (Dynamic Inputs) demonstrating working dynamic inputs
• Workarounds documented in code that other node authors can copy
• Bug documentation with root cause analysis

Installation

cd ComfyUI/custom_nodes
git clone https://github.com/YOUR_USERNAME/ComfyUI-DynamicInputsHotFix

Restart ComfyUI. Find "Dynamic Inputs" node under DynamicInputsFix category.

Workarounds for Node Authors

1. Trigger Vue Refresh Event

After modifying inputs, manually trigger the event that Vue listens for:

this.graph?.trigger?.('node:slot-links:changed', {
    nodeId: this.id,
    slotType: 1,  // INPUT
    slotIndex: slot_idx,
    connected: isConnect,
    linkId: link_info?.id ?? -1
});
this.graph?.setDirtyCanvas?.(true, true);

2. Replace Slot Object on Type Change

When changing a slot's type, replace the object to trigger Vue reactivity:

node_slot.type = parent_link.type;
this.inputs[slot_idx] = { ...node_slot };  // Creates new object reference

3. CSS for Custom Type Colors

Vue ignores color_on/color_off. Inject CSS instead:

const style = document.createElement('style');
style.textContent = `
    :root {
        --color-datatype-\\*: #888;
        --color-datatype-MYCUSTOMTYPE: #f80;
    }
`;
document.head.appendChild(style);

Known Limitations

Disconnect color bug is unfixable from extensions. When disconnecting, the new empty slot keeps the old slot's color until page refresh. This requires an upstream fix to NodeSlots.vue (using better component keys).

See COMFYUI_DYNAMIC_INPUT_BUG.md for full technical details.

License

MIT