I don't know if it is connected, but there have been several changes under the bonnet over the past few weeks, most recently an update to the latest version of MySQL in preparation for the move to VB4.
However, I have not experienced any problems on a variety of PCs and a variety of browsers.
I do think that browser add-ins and security settings account for a high proportion of oddities that are experienced. It takes a while to tailor things just so, then if one small thing changes, lots of things go peculiar.
Oh yes, and clearing out the cache and cookies...
SD