For the last two days, URLs given as part of a posting have failed to respond to my click. On this site, they turn red but that is as far as they go. On other sites they don't even do that. I have run MSE and Malwarebytes but there does not seem to be any virus infection. What might the fault be down to?
I didn't find the answer from the two hyperlinks above but then discovered the cause. The blockage was consequent upon turning the Pop-Up Blocker level from Medium to High. Back to Medium and it now works. Seems odd.