# Chatter Feed Context Considerations

When you display a canvas app inside of a feed item, the context information you receive from the signed request or from a `getContext()` call contains information specific to the feed:

- Location—If the canvas app is in the feed, then the `Environment.displayLocation` field contains the value `ChatterFeed`.
- Parameters—When you create a feed item that contains a canvas app, you can specify a JSON string as the parameters value. When the canvas app receives the context, the parameters in the feed item will be contained in the `Environment.Parameters` object.
- Size—The `Environment.Dimensions` object contains information about the size of the canvas app.

  - The canvas app height defaults to 100 pixels.

  - The canvas app width defaults to 420 pixels, which is the same as the maximum width of a canvas app in the feed.

  - The maximum height of a canvas app in the feed is 400 pixels.

  - The maximum width of a canvas app in the feed is 420 pixels.

  - This code snippet shows the default size values of a canvas app in the feed:

    ```nolang
    "dimensions":
    {
        "width": "420px",
        "height": "100px",
        "maxHeight": "400px",
        "maxWidth": "420px"
    }
    ```

  - The feed is a fixed width of 420 pixels. For example, if you resize your canvas app to be 200 pixels, the feed width remains 420 pixels.

  - You can use the `resize()` method in the Canvas SDK to change the values of your canvas app up to the `maxHeight` and `maxWidth`.

**See Also**

- [Canvas Apps in the Chatter Feed](/docs/platform/canvas-framework/guide/canvas-apps-in-chatter-feed.md)
- [Environment](/docs/platform/canvas-framework/guide/environment-object.md)
- [Dimensions](/docs/platform/canvas-framework/guide/dimensions-object.md)
- [Resizing a Canvas App](/docs/platform/canvas-framework/guide/canvas-app-resizing.md)
- [Chatter Feed Canvas App Access Considerations](/docs/platform/canvas-framework/guide/canvas-apps-chatter-feed-app-access-considerations.md)