diff --git a/package-lock.json b/package-lock.json
index 38ce1696..a2217f42 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -5370,6 +5370,16 @@
       "integrity": "sha512-jDctJ/IVQbZoJykoeHbhXpOlNBqGNcwXJKJog42E5HDPUwQTSdjCHdihjj0DlnheQ7blbT6dHOafNAiS8ooQKA==",
       "dev": true
     },
+    "bindings": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/bindings/-/bindings-1.5.0.tgz",
+      "integrity": "sha512-p2q/t/mhvuOj/UeLlV6566GD/guowlr0hHxClI0W9m7MWYkL1F0hLo+0Aexs9HSPCtR1SXQ0TD3MMKrXZajbiQ==",
+      "dev": true,
+      "optional": true,
+      "requires": {
+        "file-uri-to-path": "1.0.0"
+      }
+    },
     "bl": {
       "version": "1.2.3",
       "resolved": "https://registry.npmjs.org/bl/-/bl-1.2.3.tgz",
@@ -9432,6 +9442,13 @@
       "integrity": "sha512-qyQ0pzAy78gVoJsmYeNgl8uH8yKhr1lVhW7JbzJmnlRi0I4R2eEDEJZVKG8agpDnLpacwNbDhLNG/LMdxHD2YQ==",
       "dev": true
     },
+    "file-uri-to-path": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/file-uri-to-path/-/file-uri-to-path-1.0.0.tgz",
+      "integrity": "sha512-0Zt+s3L7Vf1biwWZ29aARiVYLx7iMGnEUl9x33fbB/j3jR81u/O2LbqK+Bm1CDSNDKVtJ/YjwY7TUd5SkeLQLw==",
+      "dev": true,
+      "optional": true
+    },
     "filename-reserved-regex": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/filename-reserved-regex/-/filename-reserved-regex-2.0.0.tgz",
@@ -9859,9 +9876,9 @@
       "dev": true
     },
     "geojs": {
-      "version": "1.10.9",
-      "resolved": "https://registry.npmjs.org/geojs/-/geojs-1.10.9.tgz",
-      "integrity": "sha512-L2GlXco5om1rlHevneVu95SwQKhWjnLW2wMHmcALY4PVUJlC0KZww6Jqs6OF4gjSnYicsIJcyJW2u20SCbyPAA==",
+      "version": "1.10.11",
+      "resolved": "https://registry.npmjs.org/geojs/-/geojs-1.10.11.tgz",
+      "integrity": "sha512-Nze5FhAkhj4nLvPGIlcWdvuD94QccKzVLU/uw2CAJuHMCRke45LpNKsypgF4Tf9mi7OCcfYPgSlKRyFPPFceJg==",
       "dev": true,
       "requires": {
         "color-name": "^1.1.4",
@@ -13864,9 +13881,9 @@
       }
     },
     "jquery": {
-      "version": "3.6.0",
-      "resolved": "https://registry.npmjs.org/jquery/-/jquery-3.6.0.tgz",
-      "integrity": "sha512-JVzAR/AjBvVt2BmYhxRCSYysDsPcssdmTFnzyLEts9qNwmjmu4JTAMYubEfwVOSwpQ1I1sKKFcxhZCI2buerfw==",
+      "version": "3.6.1",
+      "resolved": "https://registry.npmjs.org/jquery/-/jquery-3.6.1.tgz",
+      "integrity": "sha512-opJeO4nCucVnsjiXOE+/PcCgYw9Gwpvs/a6B1LL/lQhwWwpbVEVYDZ1FokFr8PRc7ghYlrFPuyHuiiDNTQxmcw==",
       "dev": true
     },
     "js-base64": {
@@ -21211,9 +21228,9 @@
       "dev": true
     },
     "vtk.js": {
-      "version": "25.6.0",
-      "resolved": "https://registry.npmjs.org/vtk.js/-/vtk.js-25.6.0.tgz",
-      "integrity": "sha512-oPinvwVyQq0jlW9+yMWtJzvCWd/6IHWAqFew3yuJhAdwoZICDePQplldE8Gjx0i76UKFQy7mVPAtf2HN+BVbPw==",
+      "version": "25.8.6",
+      "resolved": "https://registry.npmjs.org/vtk.js/-/vtk.js-25.8.6.tgz",
+      "integrity": "sha512-GLJ7Gz1mV+n0AGCC+hlc4QfR2MvB91gJ1bi9o4sKfnnSKWALRPd9jWzbZGFdVW8nqA5oFNH2L4VdYFSy5luQnA==",
       "dev": true,
       "optional": true,
       "requires": {
@@ -21782,6 +21799,7 @@
           "dev": true,
           "optional": true,
           "requires": {
+            "bindings": "^1.5.0",
             "nan": "^2.12.1"
           }
         },
@@ -22103,6 +22121,7 @@
           "dev": true,
           "optional": true,
           "requires": {
+            "bindings": "^1.5.0",
             "nan": "^2.12.1"
           }
         },
diff --git a/package.json b/package.json
index 80bc2a95..39f280b3 100644
--- a/package.json
+++ b/package.json
@@ -61,7 +61,7 @@
     "eslint": "^6.7.2",
     "eslint-plugin-prettier": "^3.1.1",
     "eslint-plugin-vue": "^6.0.1",
-    "geojs": "^1.10.4",
+    "geojs": "^1.10.11",
     "node-sass": "^7.0.1",
     "prettier": "^1.19.1",
     "pug": "^3.0.1",
diff --git a/src/components/ImageViewer.vue b/src/components/ImageViewer.vue
index 36acd760..2d66092c 100644
--- a/src/components/ImageViewer.vue
+++ b/src/components/ImageViewer.vue
@@ -200,10 +200,9 @@ export default class ImageViewer extends Vue {
   }
 
   private get mapLayerList() {
-    if (this.store.layerMode !== "unroll") {
-      return [this.layerStackImages];
-    } else {
-      const llist = [[]];
+    let llist = [this.layerStackImages];
+    if (this.store.layerMode === "unroll") {
+      llist = [[]];
       let visible = 0;
       this.layerStackImages.forEach(lsi => {
         if (visible && lsi.layer.visible) {
@@ -214,8 +213,8 @@ export default class ImageViewer extends Vue {
           visible += 1;
         }
       });
-      return llist;
     }
+    return llist;
   }
 
   /**
@@ -298,7 +297,7 @@ export default class ImageViewer extends Vue {
         map: map,
         imageLayers: [],
         params: params,
-        layerIndices: []
+        baseLayerIndex: mllidx ? undefined : 0
       };
       if (this.maps.length <= mllidx) {
         this.maps.push(mapentry);
@@ -380,9 +379,10 @@ export default class ImageViewer extends Vue {
     const mapentry = this.maps[mllidx];
     const map = mapentry.map;
     // adjust number of tile layers
-    while (mapentry.imageLayers.length > mll.length * 2) {
+    while (mapentry.imageLayers.length > mll.length * 2 || (mapentry.baseLayerIndex !== baseLayerIndex && mapentry.imageLayers.length)) {
       map.deleteLayer(mapentry.imageLayers.pop());
     }
+    mapentry.baseLayerIndex = baseLayerIndex;
     while (mapentry.imageLayers.length < mll.length * 2) {
       mapentry.params.layer.tilesAtZoom = (level: number) => {
         const s = Math.pow(2, someImage.levels - 1 - level);
@@ -403,7 +403,7 @@ export default class ImageViewer extends Vue {
        * but we run out of webgl contexts sooner than that.  Maybe because they
        * get switched on and off?
        */
-      if (currentImageLayers + this.maps.length >= 10) {
+      if (currentImageLayers + this.maps.length >= 13) {
         mapentry.params.layer.renderer = "canvas";
       } else {
         delete mapentry.params.layer.renderer;