We ran an A/B test to see how leaving sections open by default impacted reader behaviour (See T120292).
[x] We should remove the following snippet of code now we are no longer collecting this data.
```
// A/B test to measure the impact of section collapsing
if ( self.schema && self.schema.isUserInBucket() && self.schema.defaults.isTestA ) {
// Bucketed users who are in stable and using a small screen device
// will see expanded sections by default
// @see T120292
if ( context.getMode() === 'stable' && !browser.isWideScreen() ) {
expandSections = true;
}
}
```
In addition to this we should:
[x] Remove the MobileWebSectionUsage schema and all usage of it
[] Remove mediawiki configuration on Wikimedia servers.
[x] Mark the schema as disabled (https://meta.wikimedia.org/wiki/Schema:MobileWebSectionUsage )