content_aware_fill
Okay. Need to write something about this as I always forget how to go about this.
First, have the content aware tab open. Then the content aware is on the composition level and not necessarily viewer level so you need to have the footage inside a composition first. Mask the composition then perform the content aware fill.
If its a moving footage, then you have to perform the content aware fill on the whole duration But if its only one section that's moving, you can get more mileage and flexibility when only doing one content fill aware and just tracking the filled image. Or you can do both.
Reference Frame