Now why didn't I think of this?!!?
Yep, that worked and I'm now back to normal. Thanks.
It seems the default, when new people visit the site, is huge. I tried in two other browsers which I have never used on this forum before (so no cache) and it was instantly huge.
Anyway, I clicked the A and the font reduced back to what it used to be, for me.
However, when I navigated another page, the font was HUGE again. So I had to click the A again and do a Hard Refresh. Now all the pages are the same.
I note that clicking the A cycles through three font sizes - small, medium and large. However, NONE of them are HUGE, not the huge size I get when you first come to the forum or visit in a new browser.
Just thought I'd mention that.