SaveAnimatedWEBP_motorway_edition

If animated PNG is the "just works everywhere" animation format, animated WEBP is the "works everywhere and doesn't bloat the file" one. SaveAnimatedWEBP_motorway_edition clones ComfyUI's built-in SaveAnimatedWEBP and writes your image batch on the Motorway bus out as a single animated WEBP - the format Discord and basically every browser handle natively, with real compression that APNG lacks. For looping previews and short animations it's usually the better pick than APNG; only reach for APNG if a tool you need doesn't read WEBP.

One heads-up before the knobs: this is a save node riding a beta pack, and save/output nodes are exactly the category the author admits "won't work" reliably. The file is written to ComfyUI/output/, but because these clones aren't flagged as output nodes, ComfyUI's UI won't treat it as a workflow endpoint - no "final image" highlight, and you may see it behave differently than the stock node. Check your output folder, not the canvas.

The widgets:

• filename_prefix (default ComfyUI) - output file base name; supports formatting like %date:yyyy-MM-dd%.
• fps (default 6) - playback speed. 6 is the classic slow preview; 12–24 for real motion.
• lossless (default true) - lossless WEBP keeps every pixel and blows up the file; if you're doing previews, flipping this to false and leaning on quality gets you dramatically smaller files you can't tell apart at a glance.
• quality (default 80, 0–100) - only meaningful when lossless is off. 80 is a solid preview default.
• method - default, fastest, or slowest. Compression effort. Slowest squeezes the file harder at the cost of encode time; for previews, fastest is honestly fine.

The frames come off the bus by key - INPUT_images_key (default images). Type the key name where your earlier nodes parked the image batch; if you stored it under a different name, that's the string you want.

Installing it

Part of ComfyUI_agilly1989_motorway. ComfyUI Manager: search ComfyUI_agilly1989_motorway, install, restart. Or:

cd ComfyUI/custom_nodes
git clone https://github.com/agilly1989/ComfyUI_agilly1989_motorway

No extra dependencies, no model files - WEBP encoding is already inside ComfyUI's Pillow install.

The catch

The usual pack caveats, slightly amplified: release 1.1.7 ships with all *_motorway_edition clones disabled (uncomment the two ClonedNodeMapping lines in custom_nodes/ComfyUI_agilly1989_motorway/__init__.py, restart), and the README - which opens "BIG BROKEN WITH ASYNC WILL FIX WHEN I GET THE TIME/MOTIVATION" - lists output nodes among the ones that may not work. It's a neat way to keep saving on the bus, but if you're moving an existing animation pipeline over purely to save frames, the stock SaveAnimatedWEBP is the dependable choice.