diff --git a/samples/react-tree-orgchart/.devcontainer/devcontainer.json b/samples/react-tree-orgchart/.devcontainer/devcontainer.json
index edbc0aded..43357099e 100644
--- a/samples/react-tree-orgchart/.devcontainer/devcontainer.json
+++ b/samples/react-tree-orgchart/.devcontainer/devcontainer.json
@@ -1,39 +1,38 @@
-// For more information on how to run this SPFx project in a VS Code Remote Container, please visit https://aka.ms/spfx-devcontainer
 {
-	"name": "SPFx 1.10.0",
-	"image": "docker.io/m365pnp/spfx:1.10.0",
-	// Set *default* container specific settings.json values on container create.
-	"settings": {},
-	// Add the IDs of extensions you want installed when the container is created.
-	"extensions": [
-		"editorconfig.editorconfig",
-		"dbaeumer.vscode-eslint"
-	],
-	// Use 'forwardPorts' to make a list of ports inside the container available locally.
-	"forwardPorts": [
-		4321,
-		35729,
-		5432
-	],
-	"portsAttributes": {
-		"4321": {
-			"protocol": "https",
-			"label": "Manifest",
-			"onAutoForward": "silent",
-			"requireLocalPort": true
-		},
-		"5432": {
-			"protocol": "https",
-			"label": "Workbench",
-			"onAutoForward": "silent"
-		},
-		"35729": {
-			"protocol": "https",
-			"label": "LiveReload",
-			"onAutoForward": "silent",
-			"requireLocalPort": true
-		}
-	},
-	"postCreateCommand": "bash .devcontainer/spfx-startup.sh",
-	"remoteUser": "node"
-}
\ No newline at end of file
+  "name": "SPFx 1.20.0",
+  "image": "docker.io/m365pnp/spfx:1.20.0",
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "editorconfig.editorconfig",
+        "dbaeumer.vscode-eslint"
+      ]
+    }
+  },
+  "forwardPorts": [
+    4321,
+    35729,
+    5432
+  ],
+  "portsAttributes": {
+    "4321": {
+      "protocol": "https",
+      "label": "Manifest",
+      "onAutoForward": "silent",
+      "requireLocalPort": true
+    },
+    "5432": {
+      "protocol": "https",
+      "label": "Workbench",
+      "onAutoForward": "silent"
+    },
+    "35729": {
+      "protocol": "https",
+      "label": "LiveReload",
+      "onAutoForward": "silent",
+      "requireLocalPort": true
+    }
+  },
+  "postCreateCommand": "bash .devcontainer/spfx-startup.sh",
+  "remoteUser": "node"
+}
diff --git a/samples/react-tree-orgchart/.devcontainer/spfx-startup.sh b/samples/react-tree-orgchart/.devcontainer/spfx-startup.sh
index ca531bdf2..456d6aea8 100644
--- a/samples/react-tree-orgchart/.devcontainer/spfx-startup.sh
+++ b/samples/react-tree-orgchart/.devcontainer/spfx-startup.sh
@@ -7,9 +7,11 @@ echo
 echo -e "\e[1;94mGenerating dev certificate\e[0m"
 gulp trust-dev-cert
 
+# Convert the generated PEM certificate to a  CER certificate
+openssl x509 -inform PEM -in ~/.rushstack/rushstack-serve.pem -outform DER -out ./spfx-dev-cert.cer
 
-cp ~/.gcb-serve-data/gcb-serve.cer ./spfx-dev-cert.cer
-cp ~/.gcb-serve-data/gcb-serve.cer ./spfx-dev-cert.pem
+# Copy the PEM ecrtificate for non-Windows hosts
+cp ~/.rushstack/rushstack-serve.pem ./spfx-dev-cert.pem
 
 ## add *.cer to .gitignore to prevent certificates from being saved in repo
 if ! grep -Fxq '*.cer' ./.gitignore