This file is not allowed for security reasons. Can’t upload common image files

The text from the message does not exist in WordPress, so it does not come from there. But it does exist in Elementor. Have you installed Elementor? If so, that’s where to look for the cause. The reason might be that you are trying to upload an SVG image, which Elementor does not allow. You would have to contact their support for clarification: https://www.ads-software.com/support/plugin/elementor/

Thank you for the advice @threadi.