🖼💬 Save image for Bjornulf LobeChat

Let's be upfront about this one: it's the single most niche node in an already-niche pack. The author, justUmen, maintains three linked projects - a ComfyUI node pack (this one), a self-hosted chat UI fork called Bjornulf Lobe Chat, and a local text-to-speech server, Bjornulf XTTS. This save node is the bridge between the first two: it saves an image in exactly the format and location his chat fork expects, so that a message sent through his LobeChat app can trigger a ComfyUI generation and get the resulting image back inside the chat. If you're not running his LobeChat fork, this node does nothing useful for you - reach for the pack's other save nodes (Save Image to a Folder, or a plain Save Image) instead.

How it works

It saves whatever image you feed it into output/BJORNULF_LOBECHAT/, numbering sequentially - api_00001.png, api_00002.png, and so on, incrementing each run. It also drops a symlink at output/BJORNULF_API_LAST_IMAGE.png that always points at the most recent one. That symlink is the actual integration point: his LobeChat app watches that fixed path, copies whatever image is there into the chat project, and that's how a generated image ends up back in the conversation. It's a plumbing node, not a general-purpose save - it exists purely to make one specific external app work, and it's honest about that in its own name.

The inputs and outputs that matter

• image (IMAGE) - the image to hand off to LobeChat. That's the entire required input.
• No outputs. It's a terminal node in the graph - plug an image in, it writes the file and the symlink, and that's the end of that branch.

How to install it

Via ComfyUI Manager: search Bjornulf_custom_nodes, install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/justUmen/Bjornulf_custom_nodes
cd Bjornulf_custom_nodes && pip install -r requirements.txt

then restart ComfyUI. Installing this node doesn't require anything beyond the pack's normal requirements.txt - but actually making it do something requires separately setting up Bjornulf Lobe Chat, which is a whole other project with its own setup. Without that piece running, this node just quietly writes files nobody reads.

Common issues & troubleshooting

You installed the node but nothing seems to happen. That's expected if LobeChat isn't running - the node still writes output/BJORNULF_LOBECHAT/api_NNNNN.png and updates the symlink every time regardless, it just has no consumer watching for it. Check whether you actually need this node before troubleshooting it; most people looking to save an image for later use want Save Image to a Folder instead.

Filenames keep climbing even when you don't want them to. There's no toggle here to reset or overwrite - every run of the graph adds another sequential file to BJORNULF_LOBECHAT/. If you're using this outside the LobeChat integration and just want a single overwritten file, the pack's Save Image (tmp_api.png) node is closer to what you want.

Symlinks on Windows. The pack's other file-based nodes (video, TTS) are noted in the README as untested on Windows, and this integration is built around a Linux-style symlink workflow between two of the author's own projects. If you're on Windows, expect friction here before you expect it to just work.