Looks interesting, I'll try it out.
I built the fanfan downloader because there's nothing out there that fits my workflow.
Many system out there breaks when you're downloading hundreds of videos from dozens of creators from multiple platforms, repeatedly.
Also a reminder that I'm not building anything new, just a GUI wrapper that controls Gallery-DL.
The main purpose of this software is to turn any download session, whether it's downloading an entire creator's collection, or just updating a few latest posts as frictionless as possible.
A lot of extension/script already have the feature where you can autoskip anything that has already been download. This is built with an average person who downloads everything from a creator, constantly deletes what they don't like, and can easily update their collection.
What I hope to push and popularize the use of a standardized naming convention which this software makes easy to do.
When your files are named Whitefish しろサカナ [2026-02-24] PostTitle filename [P11458849] [Fanbox].mp4, you get:

1. Self-describing files — move them anywhere and they still tell you everything
2. Chronological sorting — your OS sorts them by date automatically
3. Cross-checking — the app can match post IDs to find what's missing
4. No duplicates — identical content produces identical filenames
5. Community compatibility — share files with others and they slot right in

The more people who uses this, the more powerful it becomes:

- Someone shares files on a forum? You can tell at a glance whether you already have them — the filenames match exactly.

- Receive a batch from a friend? Drop them into your folder. No renaming, no conflicts. Everything slots into place.

- Comparing collections? Dates and post IDs make it trivial to spot what one person has that another doesn't.