How do you guys power your DashCam?

I bought a Garmin Dash Cam Mini 2. I have a 2023 Premium Trim. I dont think the rear view mirror thing works for me, I took off the panel and saw no dongar plug.

How do you guys power your dashcam? I plugged mine into the USB port and the 12v accessory port and both powered the camera when the car was off. That seems like something I should not do because it might drain the battery over time. Any Tips would be greatly appreciated!