Origin
The online popularity of images of liminal spaces follows the popularity of The Backrooms meme that began in May 2019. On May 12th, 2019, an anonymous 4chan user launched a thread of “disquieting images” that “felt off” on the /x/ board, posting a photograph of an empty hallway lit by square ceiling lights and with its walls covered with monotonous yellow wallpaper. In the same thread, another user replied with a creepypasta based on the photograph, spawning the meme.
“If you’re not careful and you noclip out of reality in the wrong areas, you’ll end up in the Backrooms, where it’s nothing but the stink of old moist carpet, the madness of mono-yellow, the endless background noise of fluorescent lights at maximum hum-buzz, and approximately six hundred million square miles of randomly segmented empty rooms to be trapped in
God save you if you hear something wandering around nearby, because it sure as hell has heard you.
Precursor
Prior to the /x/ thread, several notable tweets about liminal places were made online. On May 21st, 2018, Twitter user @ReiverCafferata replied to another tweet with an explanation about liminal spaces, with their tweet gaining over 100 retweets and 1,400 likes (shown below, left). On March 15th, 2019, Twitter user @zerstoerer tweeted a photograph of the interior of a Holiday Inn Express near Heathrow Airport in London, England. The tweet (shown below, center) received over 12,000 likes and 3,000 retweets in one year, with the photograph becoming viral. On April 19th, 2019, Twitter user @unwrappedlolly created a thread about liminal spaces, with the first post in the thread gaining over 6,000 retweets and 13,100 likes (shown below, right).
Source: https://knowyourmeme.com/memes/cultures/liminal-spaces-images-with-elegiac-auras