The qffmpegencoder has an internal queue that buffers video frames when the encoder is unable to keep up with the frame source. This helps stabilizing the frame rate in case of intermittent encoder hiccups, but if the encoder is consistently unable to keep up with the frame source, the queue will grow and eventually the process will run out of memory. This happens on Windows with H264 encoding and FFMPEG plugin on a 4K monitor.
 
Reproduce
1. Run Recorder app on Windows at 4K screen resolution
2. Record data while monitoring task manager
 
Expected result
Recorder memory usage stays stable and does not grow after recording has warmed up.
 
Actual result
Recorder memory usage grows continuously