diff --git a/.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch b/.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch
new file mode 100644
index 000000000..1bfd0c31a
--- /dev/null
+++ b/.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch
@@ -0,0 +1,17 @@
+diff --git a/package.json b/package.json
+index 4619da270df88b972b4f9ea95aeffc32aa52e341..944cadb5e2ab4e1be596e76255ee4f9ae7572b18 100644
+--- a/package.json
++++ b/package.json
+@@ -16,10 +16,10 @@
+   "license": "MIT",
+   "author": "Florian Körner <contact@florian-koerner.com>",
+   "type": "module",
+-  "main": "./lib/node/index.js",
++  "main": "./lib/index.js",
+   "browser": "./lib/index.js",
+   "exports": {
+-    "node": "./lib/node/index.js",
++    "node": "./lib/index.js",
+     "default": "./lib/index.js"
+   },
+   "types": "./lib/index.d.ts",
diff --git a/frontend/src/components/common/user-avatar/default-avatar.png.license b/.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch.license
similarity index 65%
rename from frontend/src/components/common/user-avatar/default-avatar.png.license
rename to .yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch.license
index c223474fb..2053aa609 100644
--- a/frontend/src/components/common/user-avatar/default-avatar.png.license
+++ b/.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch.license
@@ -1,3 +1,3 @@
 SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
 
-SPDX-License-Identifier: CC0-1.0
+SPDX-License-Identifier: AGPL-3.0-only
diff --git a/frontend/package.json b/frontend/package.json
index 433976ed7..16cf4eee8 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -46,6 +46,8 @@
     "@codemirror/state": "6.2.1",
     "@codemirror/theme-one-dark": "6.1.2",
     "@codemirror/view": "6.20.2",
+    "@dicebear/core": "7.0.1",
+    "@dicebear/identicon": "7.0.1",
     "@fontsource/source-sans-pro": "5.0.8",
     "@hedgedoc/commons": "workspace:commons",
     "@hedgedoc/html-to-react": "workspace:html-to-react",
diff --git a/frontend/src/api/users/types.ts b/frontend/src/api/users/types.ts
index 96e6f0d92..f4ad524e6 100644
--- a/frontend/src/api/users/types.ts
+++ b/frontend/src/api/users/types.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -7,5 +7,5 @@
 export interface UserInfo {
   username: string
   displayName: string
-  photo: string
+  photoUrl: string
 }
diff --git a/frontend/src/components/common/user-avatar/__snapshots__/user-avatar.spec.tsx.snap b/frontend/src/components/common/user-avatar/__snapshots__/user-avatar.spec.tsx.snap
index 7be911f06..ecddb7e72 100644
--- a/frontend/src/components/common/user-avatar/__snapshots__/user-avatar.spec.tsx.snap
+++ b/frontend/src/components/common/user-avatar/__snapshots__/user-avatar.spec.tsx.snap
@@ -104,3 +104,47 @@ exports[`UserAvatar renders the user avatar in size sm 1`] = `
   </span>
 </div>
 `;
+
+exports[`UserAvatar uses identicon when empty photoUrl is given 1`] = `
+<div>
+  <span
+    class="d-inline-flex align-items-center "
+  >
+    <img
+      alt="common.avatarOf"
+      class="rounded user-image"
+      height="20"
+      src="data:image/x-other,identicon-mock"
+      title="common.avatarOf"
+      width="20"
+    />
+    <span
+      class="ms-2 me-1 user-line-name"
+    >
+      test
+    </span>
+  </span>
+</div>
+`;
+
+exports[`UserAvatar uses identicon when no photoUrl is given 1`] = `
+<div>
+  <span
+    class="d-inline-flex align-items-center "
+  >
+    <img
+      alt="common.avatarOf"
+      class="rounded user-image"
+      height="20"
+      src="data:image/x-other,identicon-mock"
+      title="common.avatarOf"
+      width="20"
+    />
+    <span
+      class="ms-2 me-1 user-line-name"
+    >
+      test
+    </span>
+  </span>
+</div>
+`;
diff --git a/frontend/src/components/common/user-avatar/default-avatar.png b/frontend/src/components/common/user-avatar/default-avatar.png
deleted file mode 100644
index 1f5de5740..000000000
Binary files a/frontend/src/components/common/user-avatar/default-avatar.png and /dev/null differ
diff --git a/frontend/src/components/common/user-avatar/hooks/use-avatar-url.ts b/frontend/src/components/common/user-avatar/hooks/use-avatar-url.ts
new file mode 100644
index 000000000..99f5506f4
--- /dev/null
+++ b/frontend/src/components/common/user-avatar/hooks/use-avatar-url.ts
@@ -0,0 +1,28 @@
+/*
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { useMemo } from 'react'
+import { createAvatar } from '@dicebear/core'
+import identicon from '@dicebear/identicon'
+
+/**
+ * Returns the correct avatar url for a user.
+ * When an empty or no photoUrl is given, a random avatar is generated from the displayName.
+ *
+ * @param photoUrl The photo url of the user to use. Maybe empty or not set.
+ * @param displayName The display name of the user to use as input to the random avatar.
+ * @return The correct avatar url for the user.
+ */
+export const useAvatarUrl = (photoUrl: string | undefined, displayName: string): string => {
+  return useMemo(() => {
+    if (photoUrl && photoUrl.trim() !== '') {
+      return photoUrl
+    }
+    const avatar = createAvatar(identicon, {
+      seed: displayName
+    })
+    return avatar.toDataUriSync()
+  }, [photoUrl, displayName])
+}
diff --git a/frontend/src/components/common/user-avatar/user-avatar-for-user.tsx b/frontend/src/components/common/user-avatar/user-avatar-for-user.tsx
index 9af787f71..c576d76b9 100644
--- a/frontend/src/components/common/user-avatar/user-avatar-for-user.tsx
+++ b/frontend/src/components/common/user-avatar/user-avatar-for-user.tsx
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -19,5 +19,5 @@ export interface UserAvatarForUserProps extends Omit<UserAvatarProps, 'photoUrl'
  * @param props remaining avatar props
  */
 export const UserAvatarForUser: React.FC<UserAvatarForUserProps> = ({ user, ...props }) => {
-  return <UserAvatar displayName={user.displayName} photoUrl={user.photo} {...props} />
+  return <UserAvatar displayName={user.displayName} photoUrl={user.photoUrl} {...props} />
 }
diff --git a/frontend/src/components/common/user-avatar/user-avatar.spec.tsx b/frontend/src/components/common/user-avatar/user-avatar.spec.tsx
index 3f59e1910..91cc659af 100644
--- a/frontend/src/components/common/user-avatar/user-avatar.spec.tsx
+++ b/frontend/src/components/common/user-avatar/user-avatar.spec.tsx
@@ -7,12 +7,20 @@ import type { UserInfo } from '../../../api/users/types'
 import { mockI18n } from '../../../test-utils/mock-i18n'
 import { UserAvatarForUser } from './user-avatar-for-user'
 import { render } from '@testing-library/react'
+import { UserAvatar } from './user-avatar'
+
+jest.mock('@dicebear/identicon', () => null)
+jest.mock('@dicebear/core', () => ({
+  createAvatar: jest.fn(() => ({
+    toDataUriSync: jest.fn(() => 'data:image/x-other,identicon-mock')
+  }))
+}))
 
 describe('UserAvatar', () => {
   const user: UserInfo = {
     username: 'boatface',
     displayName: 'Boaty McBoatFace',
-    photo: 'https://example.com/test.png'
+    photoUrl: 'https://example.com/test.png'
   }
 
   beforeEach(async () => {
@@ -41,4 +49,14 @@ describe('UserAvatar', () => {
     const view = render(<UserAvatarForUser user={user} showName={false} />)
     expect(view.container).toMatchSnapshot()
   })
+
+  it('uses identicon when no photoUrl is given', () => {
+    const view = render(<UserAvatar displayName={'test'} />)
+    expect(view.container).toMatchSnapshot()
+  })
+
+  it('uses identicon when empty photoUrl is given', () => {
+    const view = render(<UserAvatar displayName={'test'} photoUrl={''} />)
+    expect(view.container).toMatchSnapshot()
+  })
 })
diff --git a/frontend/src/components/common/user-avatar/user-avatar.tsx b/frontend/src/components/common/user-avatar/user-avatar.tsx
index 106e11a2e..51ea44a12 100644
--- a/frontend/src/components/common/user-avatar/user-avatar.tsx
+++ b/frontend/src/components/common/user-avatar/user-avatar.tsx
@@ -1,15 +1,15 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 import { useTranslatedText } from '../../../hooks/common/use-translated-text'
 import { ShowIf } from '../show-if/show-if'
-import defaultAvatar from './default-avatar.png'
 import styles from './user-avatar.module.scss'
 import React, { useCallback, useMemo } from 'react'
 import { OverlayTrigger, Tooltip } from 'react-bootstrap'
 import type { OverlayInjectedProps } from 'react-bootstrap/Overlay'
+import { useAvatarUrl } from './hooks/use-avatar-url'
 
 export interface UserAvatarProps {
   size?: 'sm' | 'lg'
@@ -45,9 +45,7 @@ export const UserAvatar: React.FC<UserAvatarProps> = ({
     }
   }, [size])
 
-  const avatarUrl = useMemo(() => {
-    return photoUrl || defaultAvatar.src
-  }, [photoUrl])
+  const avatarUrl = useAvatarUrl(photoUrl, displayName)
 
   const imageTranslateOptions = useMemo(
     () => ({
diff --git a/frontend/src/components/login-page/utils/fetch-and-set-user.ts b/frontend/src/components/login-page/utils/fetch-and-set-user.ts
index 6734bb3ee..6008b366e 100644
--- a/frontend/src/components/login-page/utils/fetch-and-set-user.ts
+++ b/frontend/src/components/login-page/utils/fetch-and-set-user.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -15,7 +15,7 @@ export const fetchAndSetUser: () => Promise<void> = async () => {
   setUser({
     username: me.username,
     displayName: me.displayName,
-    photo: me.photo,
+    photoUrl: me.photoUrl,
     authProvider: me.authProvider,
     email: me.email
   })
diff --git a/frontend/src/pages/api/private/me/index.ts b/frontend/src/pages/api/private/me/index.ts
index 130ae8641..4432f3014 100644
--- a/frontend/src/pages/api/private/me/index.ts
+++ b/frontend/src/pages/api/private/me/index.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -15,7 +15,7 @@ const handler = (req: NextApiRequest, res: NextApiResponse): void => {
   }
   respondToMatchingRequest<LoginUserInfo>(HttpMethod.GET, req, res, {
     username: 'mock',
-    photo: '/public/img/avatar.png',
+    photoUrl: '/public/img/avatar.png',
     displayName: 'Mock User',
     authProvider: 'local',
     email: 'mock@hedgedoc.test'
diff --git a/frontend/src/pages/api/private/users/erik.ts b/frontend/src/pages/api/private/users/erik.ts
index f42614d44..bd3855b88 100644
--- a/frontend/src/pages/api/private/users/erik.ts
+++ b/frontend/src/pages/api/private/users/erik.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -11,7 +11,7 @@ const handler = (req: NextApiRequest, res: NextApiResponse): void => {
   respondToMatchingRequest<UserInfo>(HttpMethod.GET, req, res, {
     username: 'erik',
     displayName: 'Erik',
-    photo: '/public/img/avatar.png'
+    photoUrl: '/public/img/avatar.png'
   })
 }
 
diff --git a/frontend/src/pages/api/private/users/molly.ts b/frontend/src/pages/api/private/users/molly.ts
index 36741d757..ee8d58087 100644
--- a/frontend/src/pages/api/private/users/molly.ts
+++ b/frontend/src/pages/api/private/users/molly.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -11,7 +11,7 @@ const handler = (req: NextApiRequest, res: NextApiResponse): void => {
   respondToMatchingRequest<UserInfo>(HttpMethod.GET, req, res, {
     username: 'molly',
     displayName: 'Molly',
-    photo: '/public/img/avatar.png'
+    photoUrl: '/public/img/avatar.png'
   })
 }
 
diff --git a/frontend/src/pages/api/private/users/tilman.ts b/frontend/src/pages/api/private/users/tilman.ts
index 528617ad0..039860086 100644
--- a/frontend/src/pages/api/private/users/tilman.ts
+++ b/frontend/src/pages/api/private/users/tilman.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
  *
  * SPDX-License-Identifier: AGPL-3.0-only
  */
@@ -11,7 +11,7 @@ const handler = (req: NextApiRequest, res: NextApiResponse): void => {
   respondToMatchingRequest<UserInfo>(HttpMethod.GET, req, res, {
     username: 'tilman',
     displayName: 'Tilman',
-    photo: '/public/img/avatar.png'
+    photoUrl: '/public/img/avatar.png'
   })
 }
 
diff --git a/package.json b/package.json
index d3b7c0cc7..d2758fd4e 100644
--- a/package.json
+++ b/package.json
@@ -39,7 +39,8 @@
     "eventemitter2@6.4.9": "patch:eventemitter2@npm%3A6.4.9#./.yarn/patches/eventemitter2-npm-6.4.9-ba37798a18.patch",
     "yjs@13.6.8": "patch:yjs@npm%3A13.6.8#./.yarn/patches/yjs-remove-import-warning-in-test.patch",
     "vega-canvas@^1.2.6": "patch:vega-canvas@npm%3A1.2.7#./.yarn/patches/remove-vega-canvas-node.patch",
-    "vega-canvas@^1.2.7": "patch:vega-canvas@npm%3A1.2.7#./.yarn/patches/remove-vega-canvas-node.patch"
+    "vega-canvas@^1.2.7": "patch:vega-canvas@npm%3A1.2.7#./.yarn/patches/remove-vega-canvas-node.patch",
+    "@dicebear/converter@7.0.1": "patch:@dicebear/converter@npm%3A7.0.1#./.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch"
   },
   "devDependencies": {
     "dotenv-cli": "7.3.0",
diff --git a/yarn.lock b/yarn.lock
index 77b8df62e..68900e063 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2112,6 +2112,67 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@dicebear/converter@npm:7.0.1":
+  version: 7.0.1
+  resolution: "@dicebear/converter@npm:7.0.1"
+  dependencies:
+    "@types/json-schema": ^7.0.11
+    tmp-promise: ^3.0.3
+  peerDependencies:
+    "@resvg/resvg-js": ^2.4.1
+    exiftool-vendored: ^22.0.0
+    sharp: ^0.32.1
+  peerDependenciesMeta:
+    "@resvg/resvg-js":
+      optional: true
+    exiftool-vendored:
+      optional: true
+    sharp:
+      optional: true
+  checksum: ba7b631c5ce4bd14740035465e622c4a9daf6f67ddcbff635ca8f7486a9063fe9cca47f2a4db2df53913a063a1b52df2d8015c72ac8d8a57b4e69818411845ef
+  languageName: node
+  linkType: hard
+
+"@dicebear/converter@patch:@dicebear/converter@npm%3A7.0.1#./.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch::locator=hedgedoc%40workspace%3A.":
+  version: 7.0.1
+  resolution: "@dicebear/converter@patch:@dicebear/converter@npm%3A7.0.1#./.yarn/patches/@dicebear-converter-npm-7.0.1-cb9d17808e.patch::version=7.0.1&hash=659bc7&locator=hedgedoc%40workspace%3A."
+  dependencies:
+    "@types/json-schema": ^7.0.11
+    tmp-promise: ^3.0.3
+  peerDependencies:
+    "@resvg/resvg-js": ^2.4.1
+    exiftool-vendored: ^22.0.0
+    sharp: ^0.32.1
+  peerDependenciesMeta:
+    "@resvg/resvg-js":
+      optional: true
+    exiftool-vendored:
+      optional: true
+    sharp:
+      optional: true
+  checksum: f20da5a44bed334c788568dc12fd49887de93171f71a23ba37397cdc00e693ad2bead5bed158fb06bea78ffe67c3e5c7cb611982c42da37457f319090dfbcf12
+  languageName: node
+  linkType: hard
+
+"@dicebear/core@npm:7.0.1":
+  version: 7.0.1
+  resolution: "@dicebear/core@npm:7.0.1"
+  dependencies:
+    "@dicebear/converter": 7.0.1
+    "@types/json-schema": ^7.0.11
+  checksum: 9ba71a4946ae0d4fdda9074e7f4db8c545cfb4cb13c0106517943c3de5c76618bc60eb61e01d909961c8f66f5c46b9dc03491a9f7e2075b7e9f3581980ffbac9
+  languageName: node
+  linkType: hard
+
+"@dicebear/identicon@npm:7.0.1":
+  version: 7.0.1
+  resolution: "@dicebear/identicon@npm:7.0.1"
+  peerDependencies:
+    "@dicebear/core": ^7.0.0
+  checksum: 93eb3f19b2112bcf32d6f7768fa569c080100628f90b8ecb8e633a82cdf1e943fa6ab93dc627d3631c83cb81adb643c8637d1c0f924cc7629e7d070fac6ca16d
+  languageName: node
+  linkType: hard
+
 "@emotion/cache@npm:^10.0.27":
   version: 10.0.29
   resolution: "@emotion/cache@npm:10.0.29"
@@ -2412,6 +2473,8 @@ __metadata:
     "@codemirror/state": 6.2.1
     "@codemirror/theme-one-dark": 6.1.2
     "@codemirror/view": 6.20.2
+    "@dicebear/core": 7.0.1
+    "@dicebear/identicon": 7.0.1
     "@fontsource/source-sans-pro": 5.0.8
     "@hedgedoc/commons": "workspace:commons"
     "@hedgedoc/html-to-react": "workspace:html-to-react"
@@ -4648,6 +4711,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@types/json-schema@npm:^7.0.11":
+  version: 7.0.13
+  resolution: "@types/json-schema@npm:7.0.13"
+  checksum: 345df21a678fa72fb389f35f33de77833d09d4a142bb2bcb27c18690efa4cf70fc2876e43843cefb3fbdb9fcb12cd3e970a90936df30f53bbee899865ff605ab
+  languageName: node
+  linkType: hard
+
 "@types/json5@npm:^0.0.29":
   version: 0.0.29
   resolution: "@types/json5@npm:0.0.29"
@@ -17183,6 +17253,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"tmp-promise@npm:^3.0.3":
+  version: 3.0.3
+  resolution: "tmp-promise@npm:3.0.3"
+  dependencies:
+    tmp: ^0.2.0
+  checksum: f854f5307dcee6455927ec3da9398f139897faf715c5c6dcee6d9471ae85136983ea06662eba2edf2533bdcb0fca66d16648e79e14381e30c7fb20be9c1aa62c
+  languageName: node
+  linkType: hard
+
 "tmp@npm:^0.0.33":
   version: 0.0.33
   resolution: "tmp@npm:0.0.33"
@@ -17192,7 +17271,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"tmp@npm:~0.2.1":
+"tmp@npm:^0.2.0, tmp@npm:~0.2.1":
   version: 0.2.1
   resolution: "tmp@npm:0.2.1"
   dependencies: