Files
ComfyUI_frontend/src/lib/litegraph
Christian Byrne f707098f05 fix: subgraph unpacking creates extra link to seed widget (#9046)
## Summary

Fix subgraph unpacking creating spurious links to widget inputs (e.g.
seed) when the subgraph contains ComfySwitchNode with duplicate internal
links.

## Changes

- **What**: Two fixes in `_unpackSubgraphImpl`:
1. Strip links from serialized node data **before** `configure()` so
`onConnectionsChange` doesn't resolve subgraph-internal link IDs against
the parent graph's link map (which may contain unrelated links with
colliding numeric IDs).
2. Deduplicate links by `(origin, origin_slot, target, target_slot)`
before reconnecting, preventing repeated disconnect/reconnect cycles on
widget inputs that cause slot index drift.

## Review Focus

- The link-stripping before `configure()` mirrors what
`LGraphNode.clone()` already does — nodes should be configured without
stale link references when links will be recreated separately.
- Deduplication is defensive against malformed subgraph data; the
duplicate links in the reproduction workflow likely originated from a
prior serialization bug.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9046-fix-subgraph-unpacking-creates-extra-link-to-seed-widget-30e6d73d36508125a5fefa1309485516)
by [Unito](https://www.unito.io)
2026-02-21 22:38:05 -08:00
..
2026-01-27 17:59:19 -08:00

@ComfyOrg/litegraph

This is the litegraph version used in ComfyUI_frontend.

It is a fork of the original litegraph.js. Some APIs may by unchanged, however it is largely incompatible with the original.

Some early highlights:

Usage

This library is included as a git subtree in the ComfyUI frontend project at src/lib/litegraph.

litegraph.js

A TypeScript library to create graphs in the browser similar to Unreal Blueprints.

Description of the original litegraph.js

A library in Javascript to create graphs in the browser similar to Unreal Blueprints. Nodes can be programmed easily and it includes an editor to construct and tests the graphs.

It can be integrated easily in any existing web applications and graphs can be run without the need of the editor.

Node Graph

Features

  • Renders on Canvas2D (zoom in/out and panning, easy to render complex interfaces, can be used inside a WebGLTexture)
  • Easy to use editor (searchbox, keyboard shortcuts, multiple selection, context menu, ...)
  • Optimized to support hundreds of nodes per graph (on editor but also on execution)
  • Customizable theme (colors, shapes, background)
  • Callbacks to personalize every action/drawing/event of nodes
  • Graphs can be executed in NodeJS
  • Highly customizable nodes (color, shape, widgets, custom rendering)
  • Easy to integrate in any JS application (one single file, no dependencies)
  • Typescript support

Integration

This library is integrated as a git subtree in the ComfyUI frontend project. To use it in your code:

import { LGraph, LGraphNode, LiteGraph } from '@/lib/litegraph'

How to code a new Node type

Here is an example of how to build a node that sums two inputs:

import { LiteGraph, LGraphNode } from './litegraph'

class MyAddNode extends LGraphNode {
  // Name to show
  title = 'Sum'

  constructor() {
    this.addInput('A', 'number')
    this.addInput('B', 'number')
    this.addOutput('A+B', 'number')
    this.properties.precision = 1
  }

  // Function to call when the node is executed
  onExecute() {
    var A = this.getInputData(0)
    if (A === undefined) A = 0
    var B = this.getInputData(1)
    if (B === undefined) B = 0
    this.setOutputData(0, A + B)
  }
}

// Register the node type
LiteGraph.registerNodeType('basic/sum', MyAddNode)

Server side

It also works server-side using NodeJS although some nodes do not work in server (audio, graphics, input, etc).

import { LiteGraph, LGraph } from './litegraph.js'

const graph = new LGraph()

const firstNode = LiteGraph.createNode('basic/sum')
graph.add(firstNode)

const secondNode = LiteGraph.createNode('basic/sum')
graph.add(secondNode)

firstNode.connect(0, secondNode, 1)

graph.start()

Projects using it

ComfyUI

ComfyUI default workflow

Projects using the original litegraph.js

Click to expand

webglstudio.org

WebGLStudio

MOI Elephant

MOI Elephant

Mynodes

MyNodes

Feedback

Please open an issue on the GitHub repo.

Development

Litegraph has no runtime dependencies. The build tooling has been tested on Node.JS 20.18.x

Releasing

This library is embedded via git subtree in ComfyUI_frontend. Releases are managed through the parent repository's release process.

Contributors

You can find the current list of contributors on GitHub.

Contributors (pre-fork)

  • atlasan
  • kriffe
  • rappestad
  • InventivetalentDev
  • NateScarlet
  • coderofsalvation
  • ilyabesk
  • gausszhou