WMDE Technical Wishes/Line Numbering

This page is for documenting the development progress, research and discussions about the project "Line numbering for the wikitext editor". Comments and questions are welcome on the talk page!

Line Numbering
Status Deployed on all wikis with syntax highlighting; only for the template namespace
Focus area Templates
Phabricator T267911
Responsible Technical Wishes Team


As of June 2018, Syntax highlighting uses color to make it easier to visually separate article text from the code for links, references and templates, when editing wikitext. Syntax highlighting mode can be turned on and off in the editing toolbar with the   highlighter icon. The CodeMirror software behind it is also the basis for the highlighting of matching brackets.

CodeMirror also provides the simple ability to display line numbering. This brings two main benefits - especially helpful for templates, but also applicable to other types of pages:

  • It makes it easier to refer to a line in discussions
  • It shows where line breaks are at a glance

The Technical Wishes team has therefore enabled line numbering when syntax highlighting is turned on, only in the template namespace for now.


If syntax highlighting is enabled in the editor, a gray bar with line numbering is displayed on the left edge of the editor. If syntax highlighting is disabled, then line numbering will also be disabled.

Status and roadmapEdit

  •  YApril 13-15, 2021: deployment
    • on all wikis which have syntax highlighting (CodeMirror extension). Right-to-left wikis currently aren't using CodeMirror.
    • only for the template namespace
  •  YSeptember 29, 2021: deployment on all namespaces for these wikis:
    • German Wikipedia
    • Catalan Wikipedia
    • Wikitech
    • all group 0 wikis (including mediawiki.org and testwiki)