An incredible video clip of the upcoming Xiaomi Mi Mix 4 has been leaked just as the company finally announced a release date for the smartphone. The Mi Mix 4's flexible screen panel is being tested in the video, which also reveals just how well hidden the front-facing under-display camera (UDC) is.
https://www.notebookcheck.net/Leaked-Mi-Mix-4-video-unveils-incredible-under-display-camera-on-flexible-panel-as-Xiaomi-announces-official-release-date.553140.0.html