It seems that printouts are not possible in ajax queries. This means that "population" will only be shown for Berlin and only as long as no navigation has taken place. After that, even for Berlin the "population" is gone.
So I guess that the ajax query should try to load more data, not omit the data from the original query.
Loading map...
{"format":"leaflet","minzoom":false,"maxzoom":false,"limit":50,"offset":0,"link":"all","sort":[""],"order":[],"headers":"show","mainlabel":"","intro":"","outro":"","searchlabel":"... further results","default":"","import-annotation":false,"width":"auto","height":"350px","centre":{"text":"","title":"","link":"","lat":52.5170365,"lon":13.3888599,"icon":""},"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":8,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","showtitle":true,"hidenamespace":true,"template":"","userparam":"","activeicon":"","pagelabel":false,"ajaxcoordproperty":"Coordinates","ajaxquery":"%5B%5BCategory%3ACities%5D%5D","locations":[{"text":"\u003Cb\u003E\u003Ca href=\"/wiki/Example_data:Berlin\" title=\"Example data:Berlin\"\u003EBerlin\u003C/a\u003E\u003C/b\u003E\u003Chr /\u003E\u003Ca href=\"/wiki/Property:Population\" title=\"Property:Population\"\u003EPopulation\u003C/a\u003E: 3,769,495","title":"Berlin","link":"","lat":52.517036111111,"lon":13.388861111111,"icon":""}],"imageLayers":[]}
It is kind of strange, because once you zomm ore move around, markers appear (which is great) and disappear (which ist strange) arbitrarily. This has IMO to do with the fact that due to the lack of limit= parameter in the ajax query, automatically only another couple of data is being retrieved.
