Thank you Milo and Saab Dastard.
If all else fails, trash Safari and then download again. If that fails, try downloading an earlier version. Sometimes Apple's 'improvements' to Safari don't work so well on older systems.
p.s. You could forget about a specific Apple thread. If we want to ask about Mac's we can just prefix the new thread 'Apple query'. You won't move that SD will you . . .? will you now . . . ?