Oh, well. The pop-up ad developers heard me : in the Permaculture forumn, the K-cup-coffe add is back to covering part of the text when I use "larger" text size.
And now going to "medium" and back to "larger" doesn't help on the "Permaculture" forum even thoguh I tired 'refresh' every now and then.
... but the ad is well-bahved in THIS forumn!
I can't explain it. But I may be using an unusually large effective font size: in this "reply" box, for example, a line is 86 characters wide with the IE7 "larger" text size.
If I go to "medium" it is 128 chars wide. If it is working well for most people with modern browsers, don't worry unduly about my combination.
