A while ago I installed the GoPro Webcam App, only to find out my GoPro is too old to work with it. Although I had removed the GoPro Webcam Application itself from
/Applications, the GoPro Webcam would still be shown in a list of choices.
To remove the GoPro Webcam from that list, you need to remove the file
In Finder, use SHIFT+CMD+G to navigate to
/Library/CoreMediaIO/Plug-ins/DAL/ and then remove the file
☝️ If you have other Virtual Cameras installed, you’ll also find them in that folder.
Alternatively, run this in Terminal:
sudo rm /Library/CoreMediaIO/Plug-ins/DAL/GoProWebcam.plugin
sudo is required here)
Once the file is removed removed you’ll need to restart the affected applications, as they had already loaded that plugin into memory.