Yesterday (May 26), some Facebook users saw the light for a while. And they were not too happy about it.

Quite a few users took to social media on Wednesday to report that they could no longer access Facebook's Dark Mode feature. Dark mode is a feature that shows a dark background instead of a white interface, which some people find easier to read. Dark mode can also reduce battery consumption.

If you were on Twitter on Wednesday evening, it didn't take long to find users complaining that Facebook's dark mode was unavailable. Most of the tweets about the loss of dark mode began to appear around 5 p.m. ET on Wednesday.

Dark mode has not disappeared from everyone's phone. We checked among Tom's Guide staff and found that everyone we surveyed was able to turn on Dark Mode on their iPhone or Android device.

"We are aware that some people are unable to access certain features of Facebook's Android app," a Facebook spokesperson told Tom's Guide when we contacted them about the issue." We are working to get things back to normal as soon as possible."

Shortly after midnight today (May 27), Facebook gave us the all-clear signal back. A spokesperson said, "We have restored service for those who experienced technical issues that made it difficult for some people to access certain features of the Facebook Android app."

However, some iPhone users have reported that dark mode is not working on iOS. If you are one of them, here's how to fix Facebook's dark mode issue on iPhone.

This is not the first time the issue has resurfaced in recent weeks; on May 5, some Android users reported similar problems with Facebook's Dark Mode.

You can enable Facebook's dark mode by selecting "Settings and Privacy" from the hamburger icon menu of the mobile app and heading to "Dark Mode."

If you still have issues with Facebook's dark mode, please let us know in the comments.