We just upgraded from 2.59PRO to 2.627PRO on our staging site and, for the pop-ups, the leaflet-popup-content-wrapper div class is missing from the front-end map as well as the sample map in the MPP dashboard. Happy to share screen shots if you’d like.
The plugin no longer uses the default Leaflet popups because it was difficult to get them to resize properly. Instead, I’ve switched to the custom ‘InfoBox’ popups for both Leaflet and Google. Those use a slightly different div structure. If you check the /css/mappress.css file in the plugin directory, it contains an overview of how the divs are nested.
I’m sorry for any inconvenience, and I hope that helps.