This was an arcing failure also called an arc fault.
This is where electricity leaps across a tiny gap, making the crackling noise.
In this case, it was a series arc fault, meaning electricity had to leap across an arc on its way to a normal load like an air conditioner or whatever you had plugged in. So the current flow couldn't be more than the appliances normally drew... so the circuit breaker saw normal currents, and had no reason to trip.
It is totally normal for power to be wired from supply to an outlet, then onward to another outlet, then to another, etc. As it happens, several other outlet's power came through this one. So those other outlet's usage was adding to the arc here.
Recently (last 10 years), a new type of circuit breaker was invented that listens for the electrical sounds of arcing, and shuts off the breaker. This is called an arc fault circuit interruptor or AFCI. Most on the market today are Combination AFCI, meaning they detect both shorting arcs and also our friend the series arc fault.
This is not to be confused with the dual-mode GFCI/AFCI, which is a CAFCI that also detects ground faults. Ground faults are a completely unrelated kind of failure that endangers humans by causing shocks.
AFCI breakers cost about $40US, and dual-modes about $50. Code has required AFCIs in bedrooms since 2008?? And requires them on most circuits since 2014.