Notify

You queue a 12-step Flux render, tab away to doomscroll, and by the time you look back it's been sitting idle for ten minutes. LF_Notify is the node that makes that stop: it fires a browser notification when your workflow reaches it, with a title and message you set, and - the part that makes it worth installing - buttons in the notification that can requeue the prompt, interrupt the run, or both, without you navigating back to the ComfyUI tab.

The author built this as a flagship node and it shows. The inputs are dead simple: title and message are what the notification displays. on_click_action is the dropdown that decides what clicking does - options are None, Focus tab, Interrupt, Interrupt and queue, or Queue prompt. "Interrupt and queue" is the sneaky-good one: it stops the current (probably-not-what-you-wanted) run and immediately starts the next queued prompt, which turns a wrong setting into a one-click correction. silent defaults to true, meaning no sound - flip it off if you want the ding.

There's also an image input so the notification can carry a preview (the author's demo shows a thumbnail of the result), and tag, which groups notifications: send a new notification with the same tag and it replaces the old one instead of stacking, which matters when you're iterating in a loop. The any input is pass-through data - it's why you can drop this node anywhere in a graph without breaking the flow, since the any and any_list outputs just hand it straight through.

Design it the way you'd expect: put it near the end of your pipeline, after the image processing you actually want to be notified about. Because it passes data through unchanged, you can also stick it mid-graph to mark "step one done, off to the upscaler."

Two practical notes. It's marked as an output node, so it works as a terminal node in the graph - that's expected. And a small reality check on browser notifications: they depend on ComfyUI's frontend actually being open. If the tab is closed, no notification. It's a "stop tab-switching" tool, not a "remind me while the computer sleeps" tool. The author's own framing on r/comfyui called out Notify with image previews and on-click actions as one of the pack's most useful nodes, and the requeue-from-notification loop is genuinely the killer feature.

Install: ComfyUI Manager → search "LF Nodes", or git clone https://github.com/lucafoscili/comfyui-lf into custom_nodes, then restart. No dependencies beyond the pack. Note the repo is legacy/frozen (early 2025) - still works fine - with the active version living in lucafoscili/lf-nodes.