I stayed in that time, so I think that the problem might be specific to Safari. Without getting too technical, it sounds like your session cookies might be expiring prematurely. This is definitely one for the Huddler team -- I suspect that they changed something security-wise during this last batch of updates.
Me thinks they are supposed to be making things better, not worse.
I think you might have the best answer so far.
My son buys all this expensive computer stuff, because my wife is his full time secretary, his main office is in the loft at my log house, and this iMac is in his business network with 4 others. I like that----costs me ZERO!
He thinks iMac & Safari are the best things going right now, so that is what we all use. It doesn't matter to me whether he's right or wrong, the important thing is----He's Paying!