GoReact on Canvas keeps popping up about Safari being outdated when Safari isn't outdated...how do I get rid of it?

I'm using Canvas for my teaching job. Whenever I added a new assignment for the students to create and upload their videos on the GoReact App (linked to Canvas), then I'd click on the link to set it up with GoReact (that's already created at the GoReact website and ready to be linked), it'd pop up a sign saying that Safari is outdated and need to update it. The problem is I couldn't get to the button on the bottom of the pop-up sign that's out of sign and out of reach as it's hidden behind the window to close it. It frustrates me because Safari is already updated but this annoying pop-up sign won't stop popping up. So...how do I get rid of it and/or stop it from popping up again?