diff --git a/e2e/spec/flowchart.spec.js b/e2e/spec/flowchart.spec.js
index 08ffc4a5a..5472b2946 100644
--- a/e2e/spec/flowchart.spec.js
+++ b/e2e/spec/flowchart.spec.js
@@ -40,6 +40,20 @@ describe('Flowcart', () => {
     {})
   })
 
+  it('should style nodes via a class.', async () => {
+    await imgSnapshotTest(page, `
+    graph TD
+      1A --> 1B
+      1B --> 1C
+      1C --> D
+      1C --> E
+
+      classDef processHead fill:#888888,color:white,font-weight:bold,stroke-width:3px,stroke:#001f3f
+      class 1A,1B,D,E processHead
+      `,
+    {})
+  })
+
   it('should render a flowchart full of circles', async () => {
     await imgSnapshotTest(page, `
     graph LR
@@ -145,6 +159,16 @@ describe('Flowcart', () => {
     {})
   })
 
+  it('should render subgraphs with a title startign with a digit', async () => {
+    await imgSnapshotTest(page, `
+    graph TB
+      subgraph 2Two
+        a1-->a2
+      end
+      `,
+    {})
+  })
+
   it('should render styled subgraphs', async () => {
     await imgSnapshotTest(page, `
     graph TB
diff --git a/src/diagrams/flowchart/flowDb.js b/src/diagrams/flowchart/flowDb.js
index 905615127..8570225aa 100644
--- a/src/diagrams/flowchart/flowDb.js
+++ b/src/diagrams/flowchart/flowDb.js
@@ -61,6 +61,10 @@ export const addVertex = function (_id, text, type, style, classes) {
     }
 
     vertices[id].text = txt
+  } else {
+    if (!vertices[id].text) {
+      vertices[id].text = _id
+    }
   }
   if (typeof type !== 'undefined') {
     vertices[id].type = type
@@ -175,7 +179,9 @@ export const setDirection = function (dir) {
  * @param className Class to add
  */
 export const setClass = function (ids, className) {
-  ids.split(',').forEach(function (id) {
+  ids.split(',').forEach(function (_id) {
+    let id = _id
+    if (_id[0].match(/\d/)) id = 's' + id
     if (typeof vertices[id] !== 'undefined') {
       vertices[id].classes.push(className)
     }