In the article, there's a link in the text right before they put that parenthetical. I'm guessing they're saying that the link interested them so they clicked it to read but opened it in a new tab so they could finish the current article first.

It seems to be hidden text in the page? Either way, it just shows up alongside links when you copy text from the article.

Oh interesting! That didn't even occur to me.

Probably a screen reader callout.

"microdose cocaine"