Manual:$wgDummyLanguageCodes

<translate> Language, regional and character encoding settings</translate>: $wgDummyLanguageCodes
List of language codes that have been renamed to new (correct) codes, or don't correspond to an actual interface language.
<translate> Introduced in version:</translate>	1.16.0 (r60736)
<translate> Removed in version:</translate>	<translate> still in use</translate>
<translate> Allowed values:</translate>	(array of strings)
<translate> Default value:</translate>	see below
<translate> Other settings:</translate> <translate> Alphabetical</translate> | <translate> By function</translate>

Details

This global variable contains an array of language codes that don't have a corresponding set of translated system messages and never will.

• In most cases they simply map directly to another language code. These codes are left over from renames, or other legacy things.
• "qqq" is a dummy "language" for documenting messages.
• "qqx" (since 1.18) is a dummy "language" that can be used with "&uselang=qqx" to view the message names in the interface.

These language codes are excluded on the installer as selectable user or content languages.

Since 1.18, they are excluded when running the transstat.php maintenance script (used for generating localisation statistics).

Default values

MediaWiki version:

<translate> ≥</translate> 1.19

$wgDummyLanguageCodes = [
	'als' => 'gsw',
	'bat-smg' => 'sgs',
	'be-x-old' => 'be-tarask',
	'bh' => 'bho',
	'fiu-vro' => 'vro',
	'no' => 'nb',
	'qqq' => 'qqq', # Used for message documentation.
	'qqx' => 'qqx', # Used for viewing message keys.
	'roa-rup' => 'rup',
	'simple' => 'en',
	'zh-classical' => 'lzh',
	'zh-min-nan' => 'nan',
	'zh-yue' => 'yue',
];

<td class="mw-version-versionbox" title="<translate nowrap> MediaWiki <tvar name=1>1.18</tvar> is unsupported version</translate>">

1.18

MediaWiki version:

$wgDummyLanguageCodes = array(
	'als',
	'bat-smg',
	'be-x-old',
	'fiu-vro',
	'iu',
	'nb',
	'qqq',
	'qqx',
	'roa-rup',
	'simple',
);

<td class="mw-version-versionbox" title="<translate nowrap> MediaWiki <tvar name=1>1.17</tvar> is unsupported version</translate>">

1.17

MediaWiki version:

$wgDummyLanguageCodes = array(
	'als',
	'bat-smg',
	'be-x-old',
	'dk',
	'fiu-vro',
	'iu',
	'nb',
	'qqq',
	'simple',
	'tp',
);

<td class="mw-version-versionbox" title="<translate nowrap> MediaWiki <tvar name=1>1.16</tvar> is unsupported version</translate>">

1.16

MediaWiki version:

$wgDummyLanguageCodes = array( 'qqq', 'als', 'be-x-old', 'dk', 'fiu-vro', 'iu', 'nb', 'simple', 'tp' );