I see an issue with WP-GPX-Maps ( Bastianon Massimo ) version 1.5.04 .
The issue it’s on file WP-GPX-Maps.js , line 1078 et column 5. When I see the source code I see :
hoptions.data.datasets.push( getDataset(lng.atemp,myData,Items, color7, yaxe.id) );
And for me it’s :
hoptions.data.datasets.push( getDataset(lng.atemp,myData.Items, color7, yaxe.id) );
For the support of WP-GPX-Maps, two links :
The path of the file : WP-GPX-Maps.js : wp-content/plugins/wp-gpx-maps/js/WP-GPX-Maps.js