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Parsoid Read Views is coming!

How do I keep up?

Mateus Santos / C. Scott Ananian

Content Transform Team, Wikimedia Foundation

August 8, 2025

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Parsoid and Wikitext
How you can help!
Testing, Confidence, and Feedback
Rollout Roadmap
After Read Views: Opportunities

Outline

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Parsoid and Wikitext

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Changing how articles are written (since 2012)

Wikitext is the markup language used to write articles on MediaWiki wikis.
The parser is the component which turns wikitext into HTML for browsers to display.
Parsoid is the next-generation wikitext parser; used in production since 2012 as the engine behind VisualEditor, our What-You-See-Is-What-You-Get editor.

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Wikitext -[Parsoid]-> HTML

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Changing how articles are written (since 2012)

Wikitext is the markup language used to write articles on MediaWiki wikis.
The parser is the component which turns wikitext into HTML for browsers to display.
Parsoid is the next-generation wikitext parser; used in production since 2012 as the engine behind VisualEditor, our WYSIWYG editor.

Contains a number of new features compared to the previous parser, including support for round-trip conversion from HTML back to wikitext, and preservation of semantic information.
In the process of building Parsoid we have been standardizing, documenting, and cleaning up the behavior of wikitext.

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Parsoid Answers!

“Where does this come from? What is it?”
“How do I write this in wikitext?”
“Wouldn’t it be nice if…”
“Why can’t I edit this?”

These are the sorts of questions Parsoid allows us to answer:

“Where is this coming from?” It allows us to match up the HTML in your browser and the original wikitext, so if you were to point at an item on your browser page we can tell you exactly where in the wikitext that thing came from. “What is it?” By preserving information about template boundaries and arguments and other invisible features of the wikitext, Parsoid can also provide additional meaning (“semantics”) for the things you see. For example, “this bit of HTML is an infobox”.
“How do I write this in wikitext?” Parsoid’s motto is “we deal with wikitext so you don’t have to!” Parsoid generates a stable intermediate representation which is easier for tools (and humans, in the case of Visual Editor) to write, and then takes care of all the gnarly details of how to not just /properly/ write this as wikitext, but also /elegantly/ write this as wikitext. It turns out that our editors have a keen grasp of /style/ in the wikitext they like to author on the projects, and Parsoid is careful to generate wikitext that fits in, that matches the way that human editors format their wikitext. (This varies on different projects!)
Wouldn’t it be nice if wikitext would let me write this more easily? Or if I could mark this in some way? Our ultimate goal with Parsoid is to enable new wikitext features, and we are eager to hear from you all what those ought to be.
Finally: “Why can’t I edit this?” This isn’t related to your permissions on wiki, per se, but there are certain templates which are uneditable on wiki for technical reasons: usually because they are frequently used and thus every edit to them causes the reparse of hundreds or thousands of other pages, and our servers can’t take too much of that. The incremental rendering features we are exploring in Parsoid will help reduce the backend impact of edits to these frequently used templates, and that, in turn, may allow fewer of these to be protected and thus allow you to edit more.

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Jamal Nxedlana, from Bubblegum Club, on behalf of Moleskine Foundation, CC BY-SA 4.0

Parsoid used since 2012 for

Visual Editor

Content Translation Tool

Discussion Tools

Flow

Mobile Apps

Kiwix Offline Browser

(and more!)

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Changing how articles are read (since 2024)

Maintaining multiple wikitext parsers is not sustainable!
The Parser Unification project aims to gradually replace the legacy wikitext parser entirely with Parsoid
In 2024 we began to roll out Parsoid for read views on Wikimedia wikis

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Edit Read

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2. You can join us on the transition to Parsoid Read Views!

[[Extension:ParserMigration]] is installed on WMF wikis and can be installed on any MW 1.42+ wiki and allows site-wide as well as per-user opt-in to use the new Parsoid wikitext parser.

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Parsoid opt-in using�[[Extension:ParserMigration]]

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3. Testing, Confidence, and Feedback

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The Confidence Framework

Overview

Purpose: Evaluate readiness and effectiveness for Parsoid deployment on various wikis.
Methodology: Steps and methods for comprehensive evaluations and informed Parsoid deployment decisions.

Framework's Goal

Use data to encourage deeper product inquiries.
Support fast iterations by allowing confident �experimentation and stable deployments
Transparent communication with communities by �providing the reasoning behind Parsoid Read Views roll-out

More information: https://www.mediawiki.org/wiki/Parsoid/Parser_Unification/Confidence_Framework

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Each week we do round-trip testing on tens of thousands of pages, which ensures that Parsoid can round trip a page edit from wikitext to HTML and then back to wikitext without dirty diffs.
We also use visual diff testing to compare renderings from Parsoid and the legacy parser to look for pixel-level differences in rendering.

Visual Diff and Round-trip testing

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Visual Diff Testing

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If you are using Parsoid read views, in the toolbar menu is a new item, “Report a Visual Bug”
This allows us to collect feedback from readers and editors on any rendering differences caused by Parsoid.

Report a Visual Bug

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Report a Visual Bug

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CC0, Francis Akuka for the Wikimedia Foundation

Opt in to Parsoid Read views

Preferences→Editing→�Developer Tools→�Use Parsoid: Always

Look for differences

Use sidebar to switch back to check issues
Pay special attention to dynamic behaviors & gadgets

Report bugs

[[mw:Parsoid/Parser_Unification/Known_Issues]]

How you can help!

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4. Roll-out Roadmap

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Deployment of Parsoid read views on Wikivoyage started in Fall 2024.

Wikivoyage

Parsoid was made the default render for Incubator and any newly-created wikis in Winter 2024.

Incubator and new wikis

Parsoid read views deployed on most Wiktionaries between February and April 2025.

Wiktionary

CC0, Francis Akuka for the Wikimedia Foundation

CC by SA 4.0, Alexmbogo

CC by 2.0, Nina R Africa

Parsoid on 39 low-page-view Wikipedias on July 28, 2025!

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Parsoid on

Wikipedia

We expect to complete rollout to all Wikipedias by June 2026.

Additional work beyond that point on sister projects and backend tools.

Parsoid will ship as the default wikitext parser in MediaWiki 1.47 LTS in November 2026.
Legacy parser will remain an option until next LTS (roughly November 2028).

CC0, Francis Akuka for the Wikimedia Foundation

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5. After Read Views: Opportunities

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Future of Wikitext

Wikitext is the one way the community communicates and records knowledge. The future requires a product vision for wikitext:

Syntax improvements to make authoring and editing easier
New ways of capturing meaning across languages
Better ways to reuse content to support movement inclusivity, impact, and sustainability

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Q&A