I am using QGIS 3.4.14. To inport a GPX file I usually just drag it on QGIS surface, and there I have my GPX layer with a complete attributes table (ID, elevation, time etc., plus some empty columns). Otherwise, when I inport it via the "GPS Tools" plugin (click on the icon, then Load GPX file, Feature type "Waypoints"), various attributes are missing (between them, the "time" attribute which I really need!).
Am I missing something?