Getting started
Pre-release
The plugin is below 1.0, so expect rough edges. Install the .xpi from GitHub releases, or build the current state yourself from Development setup.
What the plugin is for
You are building a chronology, and the evidence for it is already in your Zotero library. Zotero can tell you what you have read. It cannot tell you what happened, in what order, and which of your sources back each claim.
Zotero Timeline adds that layer. You author events: an event has a title, a date, an optional description, tags, and any number of links to items in your library. Each link carries a type, so a source that supports an event and a source that contradicts it are stored differently and drawn differently.
Requirements
Zotero 8, 9 or 10. The plugin declares strict_min_version 7.999 and strict_max_version 10.0.*. Zotero 7 is not supported: the plugin's menu entries are registered through Zotero.MenuManager, which Zotero 8 introduced.
The ceiling is narrow on purpose. The plugin replaces Zotero.CollectionTreeRow.prototype.getSearchObject to keep its own storage notes out of the items list, and it registers a custom Zotero_Tabs tab type whose state persists into the profile's session.json. Neither is documented API, so a Zotero major the plugin has never been tested against is likelier to break it quietly than to work. A ceiling that is too low makes the plugin absent from Tools > Plugins, which touches no data and is undone by a release; a ceiling that is too high lets it load and misbehave on top of a library.
Widening it back is a decision to make against those two call sites, not a default. Note also that it cannot be tested locally: beta and source builds ignore strict_max_version entirely, and the development profile runs a beta, so the ceiling only ever applies to users on stable builds.
The pieces you will meet
The timeline tab. One tab, opened from Tools or with shift+T, holding a horizontal chronological axis. Each timeline you have toggled on is a lane. Events are drawn on their lane at their date. Click an event to select it, then drag to change that date.
Events. Created on a timeline, never in your item list. Events are not Zotero items, so they do not appear in collections, exports, or citations. That is deliberate; Why data lives in a note explains the trade.
Dates. Dates are written in EDTF, the ISO 8601-2 extended date format, so uncertainty is expressible rather than guessed at:
| You write | It means |
|---|---|
1621 | that year |
1621? | uncertain, probably 1621 |
1580~ | approximately 1580 |
[1580..1590] | one year in that range |
1943-05/1943-06 | an interval spanning the two |
Source links. From an event, pick an item in your library and give the link a type. The starting vocabulary is cites, supports, contradicts, primary source for, and related to. You can rename, add and remove types; see the plugin data reference for where that list is kept.
The combined view. Toggle a second timeline on and both are drawn on the same axis, and both stay editable. One timeline is active at a time: it is the one your edits land on, and it is marked on the canvas so you can see where a drag will go before you make it. Click a lane, an event in it, or its row in the sidebar to make that timeline active. Toggling a timeline on does not steal the active mark, so you can bring a second chronology up for reference without losing your place.
Dragging an event from one lane into another does nothing on purpose. Moving an event between timelines is a delete and a create rather than an edit, so it goes through Duplicate in the event editor, which asks you where it should land.
The canvas goes read-only in one case: a library you can read but not write, a group library shared with you being the usual one. It says so on the surface rather than leaving you to work it out from controls that do nothing.
Where your data goes
In your library, not in a plugin config file. Each timeline is a JSON document held in the content of a Zotero note, parented to a single plugin-owned container item per library. That container keeps the notes collapsed into one row and out of Zotero's link-target picker, and that row is hidden from your item list by default.
The practical consequences are worth knowing before you start:
- Your timelines sync wherever your library syncs, with no extra setup.
- If the container item lands in the trash, your timelines vanish from the plugin until you restore it. See Recovering trashed plugin data.
- Events do not show up in Zotero's search, tag selector, or saved searches.
Where to go next
Your first timeline walks from an empty library to a timeline with a cited event. After that, the Timeline tab reference lists every control on the tab, and the sidebar groups the how-tos by where you work: the tab, your library, and Settings.