Hello Michel and welcome,
If you click to edit the image field, you will notice that there is the file extension field where you can add the allowed upload formats for your field. Try to append the .svg extension in field to see if it works.
To be honest I haven’t used svg till the day but if there is any issue with rendering the field, you can install the SVG Image module that provides extra functionalities regarding SVG format.
Let me know if that works for you,
Konstantinos