In this video I will share with you a tip from an Blog of Rogier Dijkman that example how to do it. Below is the location you will need to upload the final file
%AppData%MicrosoftTeamsBackgroundsUploads
This morning I was playing around with Microsoft Teams and wondering if it would be possible to add a gif to my custom backgrounds.
Okay, back to the subject. When looking at the supported file types in Microsoft Teams, only jpeg, jpg, png, and bmp files are allowed. So no option for animated GIF files.
https://rogierdijkman.medium.com/microsoft-teams-animated-backgrounds-b457ee38d50d