I add a new media picker and select a restriction to SVG file to test.
Set my document type property with a new field.
upload an svg file to the media area.
Under content when I create a page I select the property to upload image. It didn’t let me select the SVG file. It has a red icon. I removed this restriction and it allowed me to select.
I realised there is a bug with drag and drop so I deleted the file and added it by selecting upload in the media area but problem remains.
Did the file you uploaded get set as the Vector Graphics (SVG) type? Or was it uploaded as an Image type?
The file type restriction uses the Media Types available in Umbraco – it is not directly based on file extension. Media Types (Backoffice > Settings > Media Types) should have an Upload property that is looking for specific file extensions (which you can modify), which if there are no overlaps should be auto-catching and assigning the appropriate Media Type. But that’s where I would look if this didn’t work for you ^^
Can confirm this functionality works for v13 normally.