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/Uploads
.
I copied an animated.gif
, which is the file I want to use as my background, and an animated_thumb.jpg
to match, which is the little thumbnail I will click on to select the animated background. That said, while I could select the thumbnail, the background was still not applied.
My last hope was to rename animated.gif
to animated.jpg
to see if Microsoft Teams could be fooled into thinking it’s a static image, 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.