In a screenshotted text sent to his biographer Walter Isaacson, Musk challenged Mark Zuckerberg to an MMA fight on Monday. And — per the text — he’s even willing to cede the home octagon advantage.
“Wanna do a practice bout at your house next week?” Musk asked.
Zuckerberg — evidently sick of the runaround — essentially responded that it is time for Musk to put up or shut…