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 # Vanity
 
-This extension is currently in development.
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+The Vanity extension allows users to customize their profile in a more in-depth manner.
+
+Here is an example object:
+```json5
+{
+    // ...
+    "type": "User",
+    // ...
+    "extensions": {
+        "org.lysand:vanity": {
+            "avatar_overlay": {
+                "image/png": {
+                    "content": "https://cdn.example.com/ab5081cf-b11f-408f-92c2-7c246f290593/cat_ears.png",
+                    "content_type": "image/png"
+                }
+            },
+            "avatar_mask": {
+                "image/png": {
+                    "content": "https://cdn.example.com/d8c42be1-d0f7-43ef-b4ab-5f614e1beba4/rounded_square.jpeg",
+                    "content_type": "image/jpeg"
+                }
+            },
+            "background": {
+                "image/png": {
+                    "content": "https://cdn.example.com/6492ddcd-311e-4921-9567-41b497762b09/untitled-file-0019822.png",
+                    "content_type": "image/png"
+                }
+            },
+            "audio": {
+                "audio/mpeg": {
+                    "content": "https://cdn.example.com/4da2f0d4-4728-4819-83e4-d614e4c5bebc/michael-jackson-thriller.mp3",
+                    "content_type": "audio/mpeg"
+                }
+            },
+            "pronouns": {
+                "en-us": [
+                    "he/him",
+                    {
+                        "subject": "they",
+                        "object": "them",
+                        "dependent_possessive": "their",
+                        "independent_possessive": "theirs",
+                        "reflexive": "themself"
+                    },
+                ]
+            },
+            "birthday": "1998-04-12",
+            "location": "+40.6894-074.0447/",
+            "activitypub": "@erikuden@mastodon.de"
+        }
+    }
+}
+```
+
+The extension name is `org.lysand:vanity`. All properties are optional.
+
+## Fields
+
+### Avatar Overlay
+
+| Name           | Type          | Required |
+| :------------- | :------------ | :------- |
+| avatar_overlay | ContentFormat | No       |
+
+An overlay to be placed on top of the user's avatar. This can be used to add accessories, such as hats or glasses. Overlay should always be a transparent image.
+
+### Avatar Mask
+
+| Name        | Type          | Required |
+| :---------- | :------------ | :------- |
+| avatar_mask | ContentFormat | No       |
+
+A mask to be applied to the user's avatar. This can be used to change the shape of the avatar, such as making it a circle or a rounded square. Mask should be a fully black (#000000) image with the shape of the mask being transparent. As such, a rounded square mask should have a fully black square with rounded corners.
+
+### Background
+
+| Name       | Type          | Required |
+| :--------- | :------------ | :------- |
+| background | ContentFormat | No       |
+
+A background image to be displayed on the user's profile. This should be a full-width high-resolution image, preferably at least 1920x1080 pixels.
+
+Space-efficient formats such as WebP are recommended.
+
+### Audio
+
+| Name  | Type          | Required |
+| :---- | :------------ | :------- |
+| audio | ContentFormat | No       |
+
+An audio file to be played on the user's profile. This can be used to add a theme song or a voice introduction.
+
+> [!WARNING]
+> Audio files should be muted by default and should not autoplay. Users should have the option to play the audio file, or disable them entirely.
+>
+> Furthermore, audio file support in this extension should be toggleable per server, as it can be a potential vector for abuse.
+
+### Pronouns
+
+| Name     | Type                                 | Required |
+| :------- | :----------------------------------- | :------- |
+| pronouns | Array of ShortPronoun or LongPronoun | No       |
+
+An array of pronouns the user uses. Pronouns can be represented as a string or an object.
+
+See [Types](#types) for a full description of the `ShortPronoun` and `LongPronoun` types.
+
+### Birthday
+
+| Name     | Type   | Required |
+| :------- | :----- | :------- |
+| birthday | String | No       |
+
+The user's birthday. This should be in the format `YYYY-MM-DD` (ISO 8601). If the year is set to `0000`, clients should not display the year.
+
+Clients might choose to display the user's age as well when the year is present.
+
+### Location
+
+| Name     | Type   | Required |
+| :------- | :----- | :------- |
+| location | String | No       |
+
+The user's location. This should be a string of GPS data as defined in [ISO 6709 Annex H](https://en.wikipedia.org/wiki/ISO_6709#String_expression_(Annex_H)), or alternatively a raw string such as "New York, NY". GPS data does not need to be precise, and can be as simple as `+46+002/` (France) or `+48.52+002.20/` (Paris, France).
+
+Clients might choose to display a map of the user's location.
+
+### ActivityPub
+
+| Name       | Type   | Required |
+| :--------- | :----- | :------- |
+| activitypub | String | No       |
+
+The user's ActivityPub profile. This should be a string in the format `@username@domain`.
+
+Servers are expected to use standard WebFinger resolution to fetch the user's ActivityPub profile if needed.
+
+## Types
+
+```typescript
+interface VanityExtension {
+    avatar_overlay?: ContentFormat;
+    avatar_mask?: ContentFormat;
+    background?: ContentFormat;
+    audio?: ContentFormat;
+    pronouns?: {
+        [language: string]: (ShortPronoun | LongPronoun)[];
+    };
+    birthday?: string;
+    location?: string;
+    activitypub?: string;
+}
+```
+
+```typescript
+type ShortPronoun = string;
+```
+
+```typescript
+interface LongPronoun {
+    subject: string;
+    object: string;
+    dependent_possessive: string;
+    independent_possessive: string;
+    reflexive: string;
+}
+```
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