You probably already tried to add a new background with a .mp4 or .gif extension, but soon realized that Microsoft Teams will only allow you to select from .jpg, .jpeg, .png, and .bmp files.
I thought to myself: what if I uploaded a .mp4 or .gif to wherever Microsoft Teams stores those custom uploaded backgrounds?
A quick search lead me to ~/Library/Application Support/Microsoft/Teams/Backgrounds. I copied an animated.gif and an animated_thumb.jpg to match, and while I could select the thumbnail, the background was not applied.
My last hope was to rename animated.gif to animated.jpg, and low and behold, after selecting the thumbnail, the GIF actually played in the background.
So if you have a MP4, just convert it to a GIF, because MP4s won’t work.
There is a default.php script in /usr/local/lsws/share/autoindex that simulates Apache’s auto index, which suffices for my needs, but if you don’t want to use the default, you could copy and edit default.php to create your own template.
Now, to enable and use this auto index, you have to adjust the index directive in your website’s virtual host configuration file: