They haven’t stopped, the media just stopped reporting on them when the polls for BLM and Biden starting to go way down because of the riots.
You beat me to it. The riots have not stopped at all. In fact, they've become even more widespread. There's been quite a bit of riot and riot related action going down at night in Baltimore, especially around the Inner Harbor. Baltimore is also suffering from "food deserts" which are directly related to rioting. As Hawk said, the media—both on local and national levels—have stopped reporting riot news, save for a tidbit here or there. Beyond that, they're still rioting in many Midwest and western cities every damn night. Also, ask yourself why there's not much reporting on the California wildfires even though they have become much worse in places.