Safari v15 not working on Mac Pro 5,1 with Catalina
Solution 1:
Same problem here on MacBook Pro with Catalina. Apple Support said that they were not aware of any issues and recommended a reinstall of macOS, but that did not fix the issue as Safari is still at version 15.0. I am now considering deleting the Safari app before reinstalling again, but am not sure whether that will fix or worsen the problem.