It seems that on Jitsi Meet Google Chrome always selects 640x360 resolution
for desktop webcams even if they support higher resolutions. I tried this
with webcams supporting 1280x720, 1920x1080, 1024x768 resolutions. Google
Chrome always selected 640x360.
In Firefox 43 with default settings the resolution was 640x480, although i
could force other supported resolutions through setting explicit width and
height in the (about:config) settings "media.navigator.video.default_width"
OS: Debian Stable and Testing, Google Chrome 47.0.2526.111, Firefox 43.04