- Message broadcast: GlobalSitesChangedMessage carries site list to receivers
- Base class: FeatureViewModelBase.GlobalSites updated on message receive
- Storage tab: SiteUrl pre-filled from first global site
- Storage tab: local override prevents global from overwriting SiteUrl
- Storage tab: clearing SiteUrl reverts to global site (override reset)
- Permissions tab: SelectedSites pre-populated from global sites
- Permissions tab: local picker override blocks subsequent global updates
- Tenant switch: resets local override so new global sites apply cleanly
- Transfer tab: SourceSiteUrl pre-filled from first global site
- MainWindowViewModel: GlobalSitesSelectedLabel reflects site count