Now if you're looking for a fix for most issues where your web browser, video, audio is not working properly, try quitting out of your web browser and opening it again.
It's easy, just click the name of the browser on the very top left and click Quit
Then open the web browser again and try to login. It's amazing how often this works.
Here's couple of good reasons why this works even if it takes you a minute or two to complete:
Your browser can get confused with what you want by turning video, microphones, headphones on and off. This clears it all.
Sometimes you've got 30 tabs open and your browser is struggling to know what settings you want. It closes everything down and starts from scratch.