On macOS my experience with Zoom in the browser is that the gallery mode works in Chrome, however in Chrome it has problems with the camera (it reports that the camera is in use, or will hog the cpu and work at about 1 frame per second). On Firefox the camera works fine, but there is no gallery mode. On Safari the gallery mode and camera both work, but audio does not work! So I need to choose whether to do without video, audio, or gallery mode, or I can connect to the meeting twice with two different browsers.