Same as 'Tools/Privacy/Block Frames'
Thank you for the reply. Yes, via 'Tools/Privacy/Block Frames'.
This setting is used to create windows
and a tab is not a window.
I see...I think. Well, I wasn't getting any new window coming up (which I suppose only happens if you press CTRL+N), but they did appear in the original tab when I revisited and scrolled up through the particular forum thread in that tab some time after a few browser restarts. I'm still trying to get used to how this browser works and am unused to going into 'about:config' in browsers or using hotkeys or so many things requiring new windows instead of changing within the tab in question or just creating a new tab and exactly when those rules apply (I've only been using KM for a few months). It's a learning curve.