Well, I have an annoying bug in my version now.
So this is on the PS5 version. I tried upgrading the Rocket Science Perk to Level 3. It refuses to upgrade; just taking the slime over and over. Same with the Lucky Draw perk. I tried a run as El Tigre, got to the first boss, and after killing them, it does not continue and I have to force reboot the game; the same happens at the end of the Balloon Popping minigame. I have not tried any other fighters. Difficulty is set to "How Tough are Ya?" One extra note: I killed the boss when this issue started with a super; it was Dutchman.
I changed the difficulty, played as Azula on Master Mode; got to Pop the Balloons and after I popped the last one it stopped the timer but did not end the stage.
I started a new game. Got through the first run as normal, but once I defeated the boss, I am sent to a black screen. No victory screen, have to reboot. The campaign is entirely unplayable on my system. I pressed the input for "up special" on the black screen and heard SpongeBob's voice line for it, so presumably the stage is still loaded. In addition, the victory music and boss music are both still playing.
This issue has affected Arcade Mode, Minigames, and Boss Rush. Basically, all single player content has been rendered completely unplayable. I reported this to the Discord but have gotten no response.