L.

I get the same thing. It persists even when I switch to Twenty Nineteen and deactivate all plugins (aside from Yoast). When I turn off Yoast, it disappears.

This only happens in the Dutch version. Not the English.

I think a translation has gone wrong, because when I use Chrome Inspector Tools, I see that there a bunch of weird em tags in the div with the id #tab-panel-yst-columns. The div’s sentence starts with “Yoast SEO voegt verschillende kolommen toe aan deze pagina. We hebben een artikel geschreven over…”