diff --git a/slides/package-lock.json b/slides/package-lock.json
index a7806a2..df363c5 100644
--- a/slides/package-lock.json
+++ b/slides/package-lock.json
@@ -2948,6 +2948,12 @@
         "which": "~1.3.0"
       }
     },
+    "grunt-retro": {
+      "version": "0.6.4",
+      "resolved": "https://registry.npmjs.org/grunt-retro/-/grunt-retro-0.6.4.tgz",
+      "integrity": "sha512-kqnvNUAngOhkDckEQPYFDqNcRlculVp/Sy+gCe4ey7utM4BCaENVf2JfDeK488mj/0cgmAZyXwpW6w9l1OAxMg==",
+      "dev": true
+    },
     "grunt-sass": {
       "version": "3.0.2",
       "resolved": "https://registry.npmjs.org/grunt-sass/-/grunt-sass-3.0.2.tgz",
@@ -2955,30 +2961,13 @@
       "dev": true
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     "grunt-zip": {
-      "version": "0.17.1",
-      "resolved": "https://registry.npmjs.org/grunt-zip/-/grunt-zip-0.17.1.tgz",
-      "integrity": "sha1-IYr6NzUcRvebn7HWovw8hFGaUtA=",
+      "version": "0.20.0",
+      "resolved": "https://registry.npmjs.org/grunt-zip/-/grunt-zip-0.20.0.tgz",
+      "integrity": "sha512-W1zoPEzOYVtw5oO5eXS67QJGPuw+VdP/RcZyUZSsXVkNMP7k19aArqLkNmUjbxsE//lkryg5RteX8qsn3LC1Rg==",
       "dev": true,
       "requires": {
         "grunt-retro": "~0.6.0",
-        "jszip": "~2.5.0"
-      },
-      "dependencies": {
-        "grunt-retro": {
-          "version": "0.6.4",
-          "resolved": "https://registry.npmjs.org/grunt-retro/-/grunt-retro-0.6.4.tgz",
-          "integrity": "sha1-8mqEj2pHl6X/foUOYCIMDea+jnI=",
-          "dev": true
-        },
-        "jszip": {
-          "version": "2.5.0",
-          "resolved": "https://registry.npmjs.org/jszip/-/jszip-2.5.0.tgz",
-          "integrity": "sha1-dET9hVHd8+XacZj+oMkbyDCMwnQ=",
-          "dev": true,
-          "requires": {
-            "pako": "~0.2.5"
-          }
-        }
+        "jszip": "~2.7.0"
       }
     },
     "gzip-size": {
@@ -3674,6 +3663,23 @@
         "verror": "1.10.0"
       }
     },
+    "jszip": {
+      "version": "2.7.0",
+      "resolved": "https://registry.npmjs.org/jszip/-/jszip-2.7.0.tgz",
+      "integrity": "sha512-JIsRKRVC3gTRo2vM4Wy9WBC3TRcfnIZU8k65Phi3izkvPH975FowRYtKGT6PxevA0XnJ/yO8b0QwV0ydVyQwfw==",
+      "dev": true,
+      "requires": {
+        "pako": "~1.0.2"
+      },
+      "dependencies": {
+        "pako": {
+          "version": "1.0.11",
+          "resolved": "https://registry.npmjs.org/pako/-/pako-1.0.11.tgz",
+          "integrity": "sha512-4hLB8Py4zZce5s4yd9XzopqwVv/yGNhV1Bl8NTmCq1763HeK2+EwVTv+leGeL13Dnh2wfbqowVPXCIO0z4taYw==",
+          "dev": true
+        }
+      }
+    },
     "kind-of": {
       "version": "6.0.2",
       "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-6.0.2.tgz",
diff --git a/slides/package.json b/slides/package.json
old mode 100755
new mode 100644
index f1a2470..fad0622
--- a/slides/package.json
+++ b/slides/package.json
@@ -34,7 +34,7 @@
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     "grunt-contrib-watch": "^1.1.0",
     "grunt-sass": "^3.0.2",
-    "grunt-zip": "~0.17.1",
+    "grunt-zip": "~0.20.0",
     "load-grunt-tasks": "^4.0.0",
     "mustache": "^2.3.0",
     "node-sass": "^7.0.3",