The Import/Export tab in List Settings does four separate jobs: taking a backup, restoring one, moving a MyAnimeList list in, and moving an AniList list in.
Export Your List (backup)
The "Export List" button downloads a single JSON file named anime_list_YYYY-MM-DD.json. It contains the anime records of this installation together with your data attached to them:
Watch status, watched episode count, start and finish dates
Watch log (every change of the episode count, with its time — 1.1.46)
Notes and Personal Synopsis
Your emotion marks
Genres and sentences (by name, not by id)
Chronology markers (referring to the linked anime by its MAL/AniDB id)
Why names, not ids:
Genres, sentences and chronology targets are written with names and external ids. Record numbers differ in every installation; a backup carried by name can be restored into a different one.
Import a List
This uploads a JSON file produced by the export above. If the file is not valid JSON nothing happens and you get an error message. What happens next depends on the kind of installation:
On a multi-user site
Records in the file are matched against the catalog and the matches are added to your own list — the catalog itself is not touched. Records with no counterpart in the catalog become catalog suggestions in the moderator queue. You then get a summary: how many entries were added, how many suggestions were created, and how many had already been suggested.
On a personal (single-user) install
The backup is restored directly: anime records, genres, sentences, your personal data and chronology markers are written from the file. This is available to the owner (administrator) of the installation.
Import a MyAnimeList List
You can upload the export file you download from MyAnimeList (either the .xml or its compressed .gz form). The flow has three steps:
Choose the file and press "Preview".
Read the preview: how many records were read, how many matched the catalog, how many are already in your list, and how many have no counterpart.
Press "Import" to confirm. Nothing is written before you confirm.
The two options in the preview:Statuses to import: lets you take only the watch statuses you want (say, only "Watched"). "Overwrite entries already in my list": if left unticked, your existing entries are kept and only new ones are added. Records with no counterpart become catalog suggestions on a multi-user site, and are added directly on a personal install.
A MyAnimeList file carries a single name per anime, so entries arriving through this route do not gain a second-language title.
Import an AniList List
Here you upload nothing: you type your AniList username and your public list is fetched from AniList. Again a preview comes first, and nothing is written before you confirm.
Two Import Modes
Import the list with watch statuses — status, watched episodes, dates and notes are written into your list.
Import content only — no personal watch state is taken; only anime missing from the catalog are added as records/suggestions. Useful for growing the catalog.
The "overwrite" option only applies to the "with watch statuses" mode; in "content only" mode it is ignored.
Things to know:
The list must be public; AniList does not serve private lists. If you hit AniList's rate limit, wait a few minutes and try again. Also, the number of distinct AniList accounts is limited — you can re-sync accounts you have already imported as often as you like, but you cannot keep adding new ones.
Import Blacklist
This exists only on the multi-user site; a personal installation has no shared catalog, so it never comes into play. The problem it solves: when a moderator deleted an anime from the catalog, that anime fell into the "not in catalog" bucket of a member's next MAL / AniList import and was opened again as a catalog suggestion — deleting it made it a fresh candidate. Rejected suggestions came back with every import too.
How It Works
When an anime is deleted from the catalog, its MAL and AniDB ids are written to the blacklist automatically; entries can also be added by hand on the admin page (at least one id is required).
The MAL and AniList imports open no suggestion for a record that does not match the catalog when its id is blacklisted. The preview says "N of these are on the admin blacklist", the result says how many were skipped.
Matching is by id only, never by title — unrelated works with the same name do not block each other. A deletion record without an id stays on the list but is marked "Cannot block".
The blacklist never blocks an anime that is actually in the catalog: if the record was added again later, members can put it on their lists; the admin page marks such rows "In catalog". Adding by hand is never blocked either.
For a shared source record the id enters the list only once its last part is deleted too.
The list lives on the "Import Blacklist" page of the admin panel (moderators and above): search by title or id, undo with "Remove from list". If you want a blocked anime to be suggested by imports again, remove its entry here. The list does not travel to the central catalog and is not part of the list JSON backup; back it up as a separate file with "Export" on the same page and restore it with "Import" (it only adds, skipping what is already listed). When returning to a clean install, load this file before the first import; otherwise deleted anime are suggested again.
Clear the List
The Clear tab in List Settings deletes every anime record. The button is shown to administrators only and is really meant for personal installs: on a shared catalog it would wipe every user's data at once.
Cannot be undone:
Deleting takes everything attached to the anime with it (watch data, notes, emotions, chronology markers, filler records). The genre and sentence vocabulary survives, but its links to anime do not. Do not press this button without exporting a backup first.
For further questions: more detailed technical information is on the project's GitHub page.