All of the mapframe maps I've tested are now unclickable in both Firefox and Safari. Maplink links still work.

This appears to be because this load.php CSS was not changed when the mw-kartographer-link class was removed from the <a></a> inside the image frame (the element shows the map through its background-image CSS):

.client-js .mw-kartographer-maplink:not(.mw-kartographer-link):not(.ve-ce-focusableNode),
.client-js .mw-kartographer-map:not(.mw-kartographer-link):not(.mw-kartographer-interactive) {
 pointer-events:none;
 cursor:default
}

The old CSS classes on that element were mw-kartographer-map mw-kartographer-container floatright mw-kartographer-link. The new CSS class is mw-kartographer-map. Since the selector now matches the element, the link is disabled.

I don't know when this occurred, although the Internet Archive indicates that the change occurred between 21:08 on 18 April and 03:36 on 21 April (all times UTC).