Comet C/2023 P1 Nishimura has been in the STEREO-A HI1 field of view since September 17. It left it on October 3. A timelapse movie showing all of the frames over that period is here:
https://nickdjames.com/STEREO/comets/2023p1.mp4
Note that the frame rate changes through the movie since the cadence of frames from the spacecraft was doubled at certain points.