diff --git a/js/plot_config.js b/js/plot_config.js
index aaaebfe..f40315a 100644
--- a/js/plot_config.js
+++ b/js/plot_config.js
@@ -68,6 +68,43 @@ function updateLegend(pos) {
     }
 
     if(follow_vehicle !== null && vehicles[follow_vehicle].positions.length) {
+        // adjust index for null data points
+        var null_count = 0;
+
+        if (!map.hasLayer(polyMarker) && polyMarker) {
+            map.addLayer(polyMarker);
+        }
+
+        if(outside && pij !== undefined) {
+            if(!polyMarker) {
+                try {polyMarker = new L.Marker(vehicles[follow_vehicle].prediction_polyline.getLatLngs()[pij]).addTo(map);} catch (e) {};
+            } else {
+                try {polyMarker.setLatLng(vehicles[follow_vehicle].prediction_polyline.getLatLngs()[pij]);} catch (e) {};
+            }
+            
+        }
+        else {
+            var data_ref = vehicles[follow_vehicle].graph_data[0];
+
+            if(ij > data_ref.data.length / 2) {
+                for(i = data_ref.data.length - 1; i > ij; i--) null_count += (data_ref.data[i][1] === null) ? 1 : 0;
+                null_count = data_ref.nulls - null_count * 2;
+            } else {
+                for(i = 0; i < ij; i++) null_count += (data_ref.data[i][1] === null) ? 1 : 0;
+                null_count *= 2;
+            }
+
+            // update position
+            ij -= null_count + ((null_count===0||null_count===data_ref.nulls) ? 0 : 1);
+            if(ij < 0) ij = 0;
+
+            if(!polyMarker) {
+                try {polyMarker = new L.Marker(vehicles[follow_vehicle].positions[ij]).addTo(map);} catch (e) {};
+            } else {
+                try {polyMarker.setLatLng(vehicles[follow_vehicle].positions[ij]);} catch (e) {};
+            }
+        }
+
         // set timebox
         var date = new Date(pos.x1);
         $('#timebox').removeClass('present').addClass('past');
diff --git a/js/tracker.js b/js/tracker.js
index 157d9c7..d9eb2b5 100644
--- a/js/tracker.js
+++ b/js/tracker.js
@@ -427,7 +427,10 @@ function load() {
     receiverCanvas.addTo(map);
     
     // initalize nite overlay
-    nite = new L.terminator({ renderer: svgRenderer });
+    nite = new L.terminator({ 
+        renderer: svgRenderer,
+        interactive: false,
+    });
 
     if (offline.get("opt_daylight")) {
         map.addLayer(nite);
@@ -1260,8 +1263,12 @@ function set_polyline_visibility(vcallsign, val) {
     vehicle.polyline_visible = val;
 
     for(var k in vehicle.polyline) {
-        if (val) map.addLayer(vehicle.polyline[k]);
-        else map.removeLayer(vehicle.polyline[k]);
+        if (val) {
+            map.addLayer(vehicle.polyline[k]);
+            vehicle.polyline[k].bringToBack();
+        } else {
+            map.removeLayer(vehicle.polyline[k]);
+        }
     }
 
     map.removeLayer(mapInfoBox);
@@ -2091,6 +2098,7 @@ function addPosition(position) {
                 iconUrl: host_url + markers_url + nyan,
                 iconSize: [nyanw,39],
                 iconAnchor: [26,20],
+                tooltipAnchor: [0,-29],
             });
 
             vehicle_info.marker.setIcon(nyanIcon);
@@ -2129,8 +2137,9 @@ function addPosition(position) {
                 map.removeLayer(vehicle_info["prediction_burst"]);
             }
             try {
-                map.removeLayer(polyline[0]);
-                map.removeLayer(polyline[1]);
+                for(var p in vehicle_info.polyline) {
+                    map.removeLayer(vehicle_info.polyline[p]);
+                }
             } catch (e) {};
             for (let i = 0; i < potentialobjects.length; i++) {
                 if (map.hasLayer(potentialobjects[i])) { 
@@ -2296,7 +2305,7 @@ function updateGraph(vcallsign, reset_selection) {
     if(reset_selection) {
         if(vcallsign !== null) delete plot_options.xaxis;
 
-        if(polyMarker) map.remove(polyMarker);
+        if(polyMarker) map.removeLayer(polyMarker);
         plot_crosshair_locked = false;
 
         $("#timebox").removeClass('past').addClass('present');
diff --git a/manifest.json b/manifest.json
index 1b09984..37fe75b 100644
--- a/manifest.json
+++ b/manifest.json
@@ -3,7 +3,7 @@
   "short_name": "SondeHub",
   "description": "A webapp for tracking radiosondes.",
   "theme_color": "#00a3d3",
-  "background_color": "#33b5e5",
+  "background_color": "#00a3d3",
   "display": "standalone",
   "scope": "/",
   "start_url": "/",