This was a bonus DVD that came with a Toy.
It features a 17 minute DC Super Friends movie and 5 Imaginext episodes featuring toy characters that aren't licensed IP.
I figured that "The Joker's Playhouse" would be just like the Imaginext episodes where it was for little kids and wasn't overly interesting, but it turns out they just made a new Super Friends cartoon that is on par, as far as intensity, with the old Super Friends episodes, just utilizing the chunky designs of the toys.
Featured Heroes include, Batman, Superman, Flash, Green Lantern (Hal Jordan), Cyborg and Hawkman.
The Super Friends opening was redone, so we see Wonder Woman, Robin and Aquaman in that, but they are not in the story. There's also a Booster Gold billboard.
Featured villains include Joker, Solomon Grundy, Fr. Freeze and Gorilla Grodd.
The opening titles feature the Legion of Doom so in that we see Lex Luthor, Sinestro, Black Manta, The Cheetah, Giganta, The Scarecrow, The Toyman, The Riddler, Bizarro, Brainiac and Captain Cold.
This movie also utilizes the original Super Friends music over the opening, and then again during some action.
This is really awesome and it's really surprising DC Universe hasn't added this to their streaming service so more people can see it.