Yes, that looks like the one. Cheers.Presuming it's the pop-up below you're talking about @fulabeer then Damocles seems to believe it's caused by an Ad. I reset Chrome yesterday and have gotten the same thing this morning (just on the technical thread oddly), 3 times on the trot when switching threads.
I refresh the page through F5 rather than click on anything. I actually pay for the Ad free version of BM so that's a bit annoying :(
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