“Feature Darkmode” is Twitter’s term for turning off or hiding features on the Twitter website and/or on the API (which affects Twitter apps, meaning programs such as TweetDeck, HootSuite, etc).
Why would Twitter turn things off?
Some of the main reasons are:
- When Twitter is running slow, turning a few things off can keep the main part of the service running faster.
- When engineers are troubleshooting problems, it can help isolate issues, and let the engineers work on parts of the interface without impacting the entire service.
- When engineers are adding new features, it can give them more control to stabilize and test the system as the feature is rolled out.
So basically, this is an (admittedly annoying for users) method Twitter uses to keep things running.
What can be turned off?
Whether to stabilize the service, for testing, or to help engineers control the service when adding or fixing features, Twitter has 90+ features that can be disabled temporarily (known as feature “darkmode”). Twitter can also leave a feature turned on, but not display that feature.
A feature that is commonly limited are some kinds of advanced searches or viewing additional search pages. But Twitter can turn off or hide almost anything you can think of, including:
- Preventing usernames and hashtags from being shown as links.
- Hiding interface buttons and links, such as the retweet or delete icons.
- Hiding the “Update your profile pic” settings.
- Turning off the ability to edit Twitter Lists.
When is a Feature “Off” vs. “Broken?”
First check to see if the issue is noted on @Support. But you can’t always tell. And that’s very frustrating, particularly since Twitter would like you to report problems so they can fix them. They often rely on information from users to know when things are broken. However, there are a number of places you can check, and things you can do when you encounter a Twitter problem. The best place to start is this article on how to troubleshoot Twitter problems.