We have recently updated a community site with a new email logo (admin -> site -> email options) which was a svg
The image uploaded fine and displayed in the email templates etc, but when viewing the test emails in outlook and via mail trap the image is not being displayed.
We swapped the image to a png and all was then fine
Should svg be supported, it looked as though they were not being embedded in the email source
Additionally if a user chooses to use a svg avatar these are also not rendered in email notifications and you just see a dead link as below
e.g.
When the user uploaded a jpg avatar all is fine