Facebook App's Dark Mode Rollout on iOS Finally Gathers Pace

After months of delay and stop-start testing, Dark Mode for Facebook finally appears to be rolling out for iOS users globally, over 400 days since Apple first introduced the feature in iOS 13.
Evidence that Facebook has been working on a ‌Dark Mode‌ for its official app first surfaced in April, and by June a small percentage of users had access to the setting, which hinted that the company was gradually rolling out the feature for testing purposes.
However, propagation has been glacial