Debugging toolbar

The debugging toolbar is a utility for developers that displays debug information about a MediaWiki page at the bottom of the browser window. You can enable it with the $wgDebugToolbar variable in LocalSettings.php:

$wgDebugToolbar = true

The toolbar
The toolbar consists of multiple sections that you click to expand:
 * [[File:debugging-toolbar.png]]

The sections are:


 * Console: An area where MediaWiki code can write messages. Superior to echoing text to the browser.
 * Queries: A list of SQL queries executed on that page, with timing.
 * Debug log: A list of the debug messages printed during the page execution.
 * Request: HTTP request information.
 * PHP includes: A list of included PHP files during the page execution.
 * The rest: Statistics about the software versions, execution time, and memory used.

Logging messages to the console
See the file  for available functions. Here are a few useful examples:


 * Send an arbitrary message to the Console
 * Send an arbitrary message to the Console


 * Send a warning message to the Console
 * Send a warning message to the Console


 * Send a message to the Console about deprecated functionality, including a backtrace
 * Send a message to the Console about deprecated functionality, including a backtrace


 * Execute the given SQL and report its time in the Queries section.
 * Execute the given SQL and report its time in the Queries section.