Will portable Stratus ADS-B In receivers operate normally from the passenger cabin of a commercial airliner?
The receiver will work in the cabin but the reception is really poor. GPS will only work if it has enough satellites in view, so a window seat is best. The signal is severely attenuated by the windows.

I have brought ADS-B receivers with me on various flights but in my experience you will not get a proper ADS-B signal from aircraft further than about 20-30NM away.

Whether it is permitted or not depends on the airline and the country of operation.