Help:Extension:ParserMigration

The ParserMigration extension allows users to compare the output of the legacy wikitext parser with the latest Parsoid wikitext parser.

Enabling via user preference
This extension adds Enable parser migration tool to the list of Developer tools options at the bottom of the Editing preferences for a user.

Comparing article rendering
When this is enabled, an Edit with migration tool link is added to the Tools menu in the sidebar for article pages. Clicking this on an article page will bring up a variant of the "preview edit" page which allows you to compare the legacy parser output against Parsoid output.

Action API
This extension also adds  to the MediaWiki action API, which parses a page with two different parser configurations and returns one or both variants in the API response.