Currently gadgets by default load only on desktop, unless targets is specified in MediaWiki:Gadget-definition
Example:
confirmRollback[ResourceLoader|default|rights=rollback|dependencies=mediawiki.util]|confirmationRollback-mobile.js
Soon, the default will be changing to load on desktop AND mobile sites. We believe this is a more sensible default and will result in an improved experience for editors using the mobile site.
It is recommended (but not required) that wiki administrators audit gadget definitions prior to this change, and make the change themselves manually, in the above case by enabling the gadget on mobile and desktop like so (testing after doing so on both mobile and desktop sites):
confirmRollback[ResourceLoader|default|rights=rollback|dependencies=mediawiki.util|targets=desktop, mobile]|confirmationRollback-mobile.js
If in doubt about whether a gadget is not working on mobile, it's best to explicitly disable the gadget on the Minerva skin
confirmRollback[ResourceLoader|default|rights=rollback|dependencies=mediawiki.util|skins=vector,vector-2022,monobook,timeless,modern,cologneblue]|confirmationRollback-mobile.js
WMF will be monitoring error logs for any gadgets that are broken by this change and will take action only in the cases of widely used gadgets.