Safari crashing when clicking on downloads

Whenever I click 'any' type of download such as a file or document, safari instantly crashes, displaying a grey crash window. I even tried to download google chrome but again hitting the download button and Safari crashes. Lots of posts about enabling the developer tab and emptying caches, but there are no such options on the latest version (iMac Big sur & Safari 15.1). All help and advice forums are therefore out of date and no use.