diff --git a/server/routes/api/comments/comments.test.ts b/server/routes/api/comments/comments.test.ts
index b214a6202..394d1d95c 100644
--- a/server/routes/api/comments/comments.test.ts
+++ b/server/routes/api/comments/comments.test.ts
@@ -176,7 +176,116 @@ describe("#comments.create", () => {
       },
     });
 
+    const anotherRes = await server.post("/api/comments.create", {
+      body: {
+        token: user.getJwtToken(),
+        documentId: document.id,
+        data: {
+          type: "doc",
+          content: [{ type: "paragraph" }],
+        },
+      },
+    });
+
     expect(res.status).toEqual(400);
+    expect(anotherRes.status).toEqual(400);
+  });
+
+  it("should not allow comments containing only whitespaces", async () => {
+    const team = await buildTeam();
+    const user = await buildUser({ teamId: team.id });
+    const document = await buildDocument({
+      userId: user.id,
+      teamId: user.teamId,
+    });
+
+    const res = await server.post("/api/comments.create", {
+      body: {
+        token: user.getJwtToken(),
+        documentId: document.id,
+        data: {
+          type: "doc",
+          content: [
+            {
+              type: "paragraph",
+              content: [{ type: "text", text: "  \n\r\n" }],
+            },
+          ],
+        },
+      },
+    });
+
+    expect(res.status).toEqual(400);
+  });
+
+  it("should allow adding images to comments", async () => {
+    const team = await buildTeam();
+    const user = await buildUser({ teamId: team.id });
+    const document = await buildDocument({
+      userId: user.id,
+      teamId: user.teamId,
+    });
+
+    const res = await server.post("/api/comments.create", {
+      body: {
+        token: user.getJwtToken(),
+        documentId: document.id,
+        data: {
+          type: "doc",
+          content: [
+            {
+              type: "paragraph",
+              content: [
+                {
+                  type: "image",
+                  attrs: {
+                    src: "https://example.com/image.png",
+                    alt: "Example image",
+                  },
+                },
+              ],
+            },
+          ],
+        },
+      },
+    });
+
+    expect(res.status).toEqual(200);
+  });
+
+  it("should allow adding images from internal sources", async () => {
+    const team = await buildTeam();
+    const user = await buildUser({ teamId: team.id });
+    const document = await buildDocument({
+      userId: user.id,
+      teamId: user.teamId,
+    });
+
+    const res = await server.post("/api/comments.create", {
+      body: {
+        token: user.getJwtToken(),
+        documentId: document.id,
+        data: {
+          type: "doc",
+          content: [
+            {
+              type: "paragraph",
+              content: [
+                {
+                  type: "image",
+                  attrs: {
+                    src: "/api/attachments.redirect?id=1401323b-c4e2-40de-b172-e1668ec89111",
+                    alt: null,
+                  },
+                },
+              ],
+            },
+          ],
+        },
+      },
+    });
+
+    expect(res.status).toEqual(200);
   });
 
   it("should not allow invalid comment data", async () => {
diff --git a/server/routes/api/schema.ts b/server/routes/api/schema.ts
index a22393216..d44772f01 100644
--- a/server/routes/api/schema.ts
+++ b/server/routes/api/schema.ts
@@ -2,6 +2,7 @@ import formidable from "formidable";
 import { Node } from "prosemirror-model";
 import { z } from "zod";
 import { ProsemirrorData as TProsemirrorData } from "@shared/types";
+import { ProsemirrorHelper } from "@shared/utils/ProsemirrorHelper";
 import { schema } from "@server/editor";
 
 export const BaseSchema = z.object({
@@ -14,7 +15,7 @@ export const ProsemirrorSchema = z.custom<TProsemirrorData>((val) => {
   try {
     const node = Node.fromJSON(schema, val);
     node.check();
-    return true;
+    return !ProsemirrorHelper.isEmpty(node, schema);
   } catch (_e) {
     return false;
   }
diff --git a/shared/editor/nodes/Image.tsx b/shared/editor/nodes/Image.tsx
index d67efc302..ba4b32860 100644
--- a/shared/editor/nodes/Image.tsx
+++ b/shared/editor/nodes/Image.tsx
@@ -166,6 +166,8 @@ export default class Image extends SimpleImage {
           ["p", { class: "caption" }, 0],
         ];
       },
+      toPlainText: (node) =>
+        node.attrs.alt ? `(image: ${node.attrs.alt})` : "(image)",
     };
   }
 
diff --git a/shared/utils/ProsemirrorHelper.ts b/shared/utils/ProsemirrorHelper.ts
index b2aa0f470..bc18cdfef 100644
--- a/shared/utils/ProsemirrorHelper.ts
+++ b/shared/utils/ProsemirrorHelper.ts
@@ -142,8 +142,35 @@ export class ProsemirrorHelper {
    *
    * @returns True if the editor is empty
    */
-  static isEmpty(doc: Node) {
-    return !doc || doc.textContent.trim() === "";
+  static isEmpty(doc: Node, schema?: Schema) {
+    if (!schema) {
+      return !doc || doc.textContent.trim() === "";
+    }
+
+    const textSerializers = Object.fromEntries(
+      Object.entries(schema.nodes)
+        .filter(([, node]) => node.spec.toPlainText)
+        .map(([name, node]) => [name, node.spec.toPlainText])
+    );
+
+    let empty = true;
+    doc.descendants((child: Node) => {
+      // If we've already found non-empty data, we can stop descending further
+      if (!empty) {
+        return false;
+      }
+
+      const toPlainText = textSerializers[child.type.name];
+      if (toPlainText) {
+        empty = !toPlainText(child).trim();
+      } else if (child.isText) {
+        empty = !child.text?.trim();
+      }
+
+      return empty;
+    });
+
+    return empty;
   }
 
   /**