• Elon Musk mocked a t-shirt with the hashtag #StayWoke, meant to support the BLM movement.

• Musk then posted a picture of a shirt with the modified slogan #Stay@Work.

• Since taking over at Twitter, employees say they've been asked to work brutally long hours.

Billionaire and new Twitter owner Elon Musk further mocked the company's previous efforts to support the Black Lives Matter movement — while also making light of his own demands on employees.

A Wednesday Twitter post from Musk featured a photo of a black t-shirt with the phrase "#Stay@Work" across the front, appearing to poke fun at the #StayWoke shirts he found at the Twitter HQ and posted about on Tuesday.

The phrase "#Stay@Work" phrase likely points to reports of brutally long work weeks, mass layoffs, and mass resignations under Musk's new leadership.

The original "Stay Woke" shirts were made in support of the Black Lives Matter Movement, which took off in 2016. The company's co-founder, Jack Dorsey, wore the shirt the same year during an interview.

Dorsey said at the time that the hashtag represents, "being aware, staying aware [of] what you're seeing on the TV screen [in Ferguson] versus what's happening on the ground," referring to the police killing of 18-year-old Michael Brown in Ferguson, Missouri.

"Here we are at the merch … and there's an entire closet full of hashtag woke t-shirts," Musk said in the video showing off the old shirts in a tweet on Tuesday.

As of Wednesday night, Musk's post about the new apparel had more than 27.5k retweets, more than 4k quote tweets, and more than 297.4k likes.

In a now-deleted tweet with a 2015 report from the US Department of Justice, Musk said, "'Hands up don't shoot' was made up. The whole thing was a fiction," Bloomberg reported Wednesday.