Britney Spears is backing her old fling Wade Robson for opening up about his past trauma of allegedly being molested as a kid — and Michael Jackson fans are furious about it.The singer posted — and then deleted — a B&W vid of Wade talking about his podcast “Trauma to Triumph” … and, in true Brit fashion, began rambling about how his story hit her right in the feels, and why she totally understood what he was saying.

BS explained it warmed her heart to see an “older man” opening up about his challenges, sparking the whole reflection about her own troubled past.

Despite Wade actually being a year younger than her at 41, Brit once again tried to make out he was like a senior citizen … saying, “It genuinely touched my heart to see this older man speak on something that’s incredibly sensitive to my heart.”While Britney was getting all sentimental, the King of Pop’s fans were straight-up furious at her for speaking so highly of Wade — who has long claimed Jackson befriended him and sexually abused him when he came over to the U.S. from Australia as a young kid.

MJ fans popped off on Britney big time for her post — some said it was embarrassing and shameful for her to post such a thing since MJ had helped boost her career … and others reminded her he was no longer around to defend himself.

HBO

Of course, Wade and MJ’s other longtime accuser, James Safechuck, are still gearing up to have their day in court as part of their revived lawsuit against the late singer’s estate.

As for Britney’s other connection to Wade, they go way back … as he’s the guy she cheated with while dating Justin Timberlake. She spilled the beans about their affair in her ‘Woman in Me’ memoir — but folks have known ever since JT dropped “Cry Me a River.”