Don’t piss off, CAPTAIN KIRK as WILLIAM SHATNER launches salvo against MARK ZUCKERBERG’s new CELEBS ONLY Facebook app.

Twitter King Bill was less than pleased when he blogged about Facebook’s new “must have” app “Mentions” which allows fans to interact on the social media sans the usual morass of FB clutter.

How annoyed was Shat the Man? He tore the app a proverbial new on one on his Tumblr blog.

 “I’m not quite sure why Facebook released this app for ‘celebrities,’ ” Shatner wrote. “It seems to be ill-conceived.”

Among things that irked him: Mentions requires its “actors, athletes, musicians and other influencers” to follow other celebs as part of the registration process.

And the first celeb recommended to Shatner?

Why, his “Star Trek” nemesis and rage baiting "King of Meme" George Takei .

“Rolling my eyes,” Shatner wrote about Facebook’s suggestion that he follow Takei.

Shatner chose Robert Downey Jr. instead — and then promptly hid his posts, he said.

“I think that is a big flaw in the set-up. If this app is for celebrities then WHY force them to follow another celebrity in order to set up this app?” Shatner said.