Load Flux VAE

This one's small and single-purpose, and the thing to know about it isn't really "what it does" - it's "what it can't connect to." FluxVAELoader loads a Flux Fill VAE file so it can feed FluxTransformerInpainting and FluxGuffInpainting, the two "bring your own VAE" nodes in rubi-du's ComfyUI-Flux-Inpainting pack. That's it, that's the whole job.

What it's for and where it fits

ComfyUI-Flux-Inpainting wraps Black Forest Labs' FLUX.1 Fill dev - the purpose-trained inpainting/outpainting model, still the reference point for masked editing even now that instruction-editing models handle a lot of the simpler "just change this" jobs. The pack ships two ways of running it: monolithic nodes (FluxInpainting, FluxSimpleInpainting) that load their own VAE internally, and split nodes (FluxTransformerInpainting, FluxGuffInpainting) where you supply the VAE yourself. FluxVAELoader exists purely to fill that second role - it's the node the pack added (per its own changelog, alongside FluxSimpleInpainting and FluxTransformerInpainting) specifically so people could reuse standard ComfyUI-style loading instead of the all-in-one nodes doing everything behind the scenes.

The one thing to watch: its output type

Input: vae_name - a dropdown of files in ComfyUI/models/vae.

Output: vae, typed AUTOENCODER.

That output type is the whole reason this node exists as its own thing rather than you just using ComfyUI's built-in VAE loader. AUTOENCODER is a custom type this pack defines - it is not the same as ComfyUI's native VAE type, and it will not connect to a stock VAEDecode or VAEEncode node. It only wires into the vae inputs on FluxTransformerInpainting and FluxGuffInpainting, the two sibling nodes in this same pack. If you're trying to use this loader anywhere else in your graph, that's the mismatch - swap in ComfyUI's regular VAELoader instead for anything outside this pack.

Installing it

Comes bundled with the rest of the pack - there's no separate install. Get it through ComfyUI Manager by searching "ComfyUI-Flux-Inpainting", or manually:

cd ComfyUI/custom_nodes
git clone https://github.com/rubi-du/ComfyUI-Flux-Inpainting.git
cd ComfyUI-Flux-Inpainting
pip install -r requirements.txt

then restart ComfyUI. The pip install step matters for the pack as a whole (it needs diffusers and bitsandbytes to load the other nodes' quantized models) even though this particular loader node is simple enough not to need much beyond that.

For the model file itself, download the Flux Fill VAE from BFL's official repo and drop it in ComfyUI/models/vae. It'll then show up in the vae_name dropdown.

Where people get stuck

• "Can't connect vae to VAEDecode." Expected - AUTOENCODER isn't ComfyUI's native VAE type. This loader is scoped to this pack's own inpainting nodes only.
• Dropdown is empty. Means nothing's in ComfyUI/models/vae yet, or the file you downloaded landed in the wrong folder (this needs the plain vae directory, not a subfolder inside FLUX.1-Fill-dev).
• Using the wrong VAE. Make sure it's specifically the Flux Fill VAE, not a generic SDXL or standard Flux Dev VAE - Flux Fill's own encode/decode is what the rest of the pipeline expects.
• Not sure if you need this node at all. If you're using FluxInpainting, Flux-Inpainting, or FluxSimpleInpainting, you don't - those load VAE internally. Only reach for this loader when you're using FluxTransformerInpainting or FluxGuffInpainting.
• Pack is frozen at December 2024. Don't expect active maintenance here; it's a stable, unmaintained snapshot at this point.