[Bug]: Multiple links from legacy reroute create separate slots instead of sharing one when dropped on SubgraphOutputNode

[christian-byrne]

Prerequisites

• I am running the latest version of ComfyUI
• I have searched existing issues to make sure this isn't a duplicate
• I have tested with all custom nodes disabled

What happened?

When dragging multiple links from the output slot of a legacy reroute node (using shift-drag) and dropping them onto a SubgraphOutputNode, each link creates its own new slot instead of all links connecting to a single slot. This is inconsistent with the expected behavior where multiple links should share the same slot when dropped together.

Steps to Reproduce

1. Create or enter a subgraph
2. Add a legacy reroute node (not the new dot-style reroute)
3. Connect the reroute's output to multiple different node inputs
4. Hold Shift and drag from the reroute's output slot (this grabs all connected links)
5. Drop the links onto the SubgraphOutputNode
6. Observe: Each link creates its own new output slot on the SubgraphOutputNode
7. Expected: All links should connect to a single output slot

How is this affecting you?

Feature doesn't work as expected

ComfyUI Frontend Version

1.26.0

Browser

Chrome/Chromium

Console Errors

No console errors are generated - this is a behavioral issue.

Additional Context

The issue appears to be in the method in . When multiple links are being dropped, the method doesn't distinguish between:

1. Dropping on an existing slot (should connect all links to that slot)
2. Dropping on the EmptySubgraphOutput slot (currently creates a new slot for each link)

The expected behavior would be:

• If dropping multiple links on an existing slot: connect all to that slot
• If dropping on empty space/EmptySubgraphOutput: create ONE new slot and connect all links to it

This inconsistency makes it difficult to efficiently connect multiple outputs through a reroute node to a single subgraph output slot.

Note: This issue is specific to legacy reroute nodes. The behavior may differ with the newer dot-style reroute nodes.

┆Issue is synchronized with this Notion page by Unito