Long-term friendships have their peaks and valleys, even the ones that play out on social media.
Elon Musk and Jim Cramer have previously had a pretty friendly relationship in public, so maybe the jab Musk took at Cramer Friday morning was all in good fun.
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While Musk's response is a bit cryptic for the layperson, for the chronically online it screams "inverse Cramer."
Inverse Cramer started off as an online meme stating that betting against Jim Cramer's stock recommendations was the quickest way to make money in the stock market.
That meme gave way to the Inverse Cramer Tracker ETF, which actively allows investors to bet against Cramer stocks by shorting the ones he recommends on Twitter and CNBC.
So when Musk tweets a birthday celebration emoji at Cramer after he pumps the Nasdaq with a tweet, it doesn't take a Musk expert to read between the lines and see what he's talking about.
CNBC's Jim Cramer has previously been a pretty big booster of Elon Musk the personality as well as Elon Musk the Tesla executive. But as the scrutiny on Musk has has been turned up, Cramer's support of him has been turned down.
Cramer, for his part, says he doesn't really care if people bet against him.