If you’re a grandma or grandpa, be careful how you sign your Facebook messages.

Hundreds of grandparents have been posting in the name of legendary hip-hop DJ Grandmaster Flash.

The posts – a mixed bag of birthday and graduation wishes, back to school comments, thank you messages for splendid outings and dinners, “I love yous” and even a pie recipe – are fairly innocuous except for the signoff: “Love Grandpa and Grandmaster Flash” or just “Love Grandmaster Flash.”

Has a new demographic suddenly discovered the aging DJ (real name: Joseph Saddler), decades after he and his rap crew the Furious Five hit it big with a track titled, coincidentally, “The Message”?

No. The truth  is a lot more “adorable,” to borrow a word the DJ himself used in a recent video he tweeted upon discovering the reason for his unexpected fan base. It seems that the messages are accidental, a glitch that occurs when novice techies inadvertently activate the Facebook “autofill” function, which helps users tag their friends more easily when submitting posts.
 

 
See for yourself: Just type the word “Grandm-” and watch how quickly Facebook overzealously tacks on  “-aster Flash.” Hit send without looking, and you’ve now “tagged” the DJ. Your post not only ends up on his page, it also puts you in the running to be included in the hilarious new Tumblr, “Love, Grampa and Grandmaster Flash.”

Now that the word is out, Grandmaster Flash, 56, is showing his solidarity with the elders by including grandparents in a selfie contest he started a month ago. The prize: copies of his latest album. “Grab your grandma or grandpa, take a selfie with them and post it on social media with #FlashASelfie,” his page posted yesterday. “We’re randomly picking 20 lucky winners.”

 
Sometimes it pays to be a tech newbie.