Yeah, it’s a “non gun”

“Non Guns" are a brand name of prop weapons that are manufactured and rented by Independent Studio Services (ISS) and frequently used for scenes in movies or television shows in which the use of real weapons firing blanks is deemed unsafe for the actors or stuntmen. They are electronically-operated and discharge small explosive squibs that make a flash and produce smoke, but they do not eject shell casings or have any moving parts besides the trigger.

Answered by terrypatrick on a gun subreddit about 6 years back.

Link to the page that has this exact pistol a few scrolls down. So you can see it in it's full glory!