Who: MonoBook has a preference that displays viewport adapting behaviour on mobile devices. If you use this, at a future date, this will temporarily stop working without any action.
In T285402, the MonoBook preference was generalized to become a preference that applies to all skins and in several weeks time it will apply to MonoBook replacing the existing preference.
How: TO see if you are impacted visit [[ Special:Preferences ]] and check if the "Enable responsive MonoBook design" is unticked like so:
{F34534924}
If it is, you will need to untick the box "Enable responsive mode":
{F34534928}
Note project admins can automate this migration with the following temporary code inside MediaWiki:MonoBook.js:
```
/**
* Monobook preference migration code.
*/
function updateCorePreferenceIfMonobookSet() {
var api = new mw.Api();
var val = mw.user.options.get( 'skin-responsive' );
var skinResponsiveNotSet = val !== 0;
var api = new mw.Api();
// No viewport detected in HTML and new MediaWiki core preference is not set.
if ( !$( 'meta[name=viewport]' ).length && skinResponsiveNotSet ) {
api.saveOption( 'skin-responsive', 0 );
}
}
$( updateCorePreferenceIfMonobookSet );
```
# Note about db migration
The number of users impacted is quite low, but we could run a database migration if we prefer, migrating monobook-responsive preference to skin-responsive.