Zoom web client video trouble

[Cubiking]

Hi everyone,

Recently I tried to use Zoom on an old laptop. The os is 32 bit Antix 19.5 (Debian based). I use the web client on Firefox 89 32 bit. The audio works fine. Others can see the screen I shared. However, I could not see the camera and the shared screen of other people. There are signs indicating that other is sharing the screen or switch on the camera, such as the green bar or the disappearance of user icon. Could anyone help me?