[uasnew]

Is there a way to make a gopro act as a webcam in linux? (not with wifi, preferably with usb 3?)

[vetinari]

GoPro streaming has too high latency, but if it is fine for you, the utility in the linked repo can do udp streaming.

For low-latency streaming, a better bet would be HDMI capture card or dongle and using HDMI-out on the GoPro.

[konraditurbe]

Yes, use a HDMI capture card and have it interface using /dev/videoN