• Android version: 8.1.0
• Briar version: 0.16.19
• Phone model: LeEco LEX720 (ZL1_CN)
• User feedback: "Adding a first contact fails."

The log shows that the camera is receiving preview frames and decoding them quickly, but no QR code is found. Probably a one-off, but I'm recording this in case it indicates a problem (e.g. selecting the wrong camera or cropping the wrong part of the preview image).