[SharePoint Copilot Apps preview] " IFrame/container height remains same in expand and collapse mode

[HarminderSethi]

Target SharePoint environment

SharePoint Online

What SharePoint development model, framework, SDK or API is this about?

💥 SharePoint Framework

Developer environment

Windows

What browser(s) / client(s) have you tested

• 💥 Internet Explorer
• 💥 Microsoft Edge
• 💥 Google Chrome
• 💥 FireFox
• 💥 Safari
• mobile (iOS/iPadOS)
• mobile (Android)
• not applicable
• other (enter in the "Additional environment details" area below)

Additional environment details

SPFx version. 1.24.0-beta.2
Node.js version : v22.21.1

Describe the bug / error

When an SPFx Copilot Component is rendered inside Microsoft 365 Copilot, the component iframe appears to use the same height in both collapsed and expanded states.

Expanding the component does not trigger a resize of the iframe/container height. As a result, the expanded view is constrained to the same height as the collapsed view.

From browser inspection, the iframe is rendered with a fixed height value:

Steps to reproduce

1. Create and deploy an SPFx Copilot Component.
2. Open Microsoft 365 Copilot.
3. Trigger a response that renders the component.
4. Observe the component in collapsed state.
5. Expand the component.
6. Inspect the generated iframe/container element.

Expected behavior

The iframe/container height should be recalculated when the component is expanded so that the expanded content can be fully displayed.

[Ashlesha-MSFT]

Hello Harminder Singh (@HarminderSethi)
Thank you for bringing this issue to our attention. We will look into it and get back to you shortly.

[Ashlesha-MSFT]

Harminder Singh (@HarminderSethi)
I tried to reproduce this issue with the same/general setup, but I’m not seeing the reported behavior.

In my case, the iframe/container height changes when switching between the collapsed and expanded states, and the expanded view is not constrained to the collapsed height.

Could you please share any additional details about the environment or repro steps that might be required to consistently reproduce the issue?

[RajSharePoint]

I have been facing this for last 3 days. The response container height is locked. Even when i try to expand it, the height remains same.

[jansenbe]

Harminder Singh (@HarminderSethi) / RajSharePoint : did you try to explicitly resize the host iframe using below code:

const wasSent: boolean = await onRequestSizeChange(nextSize.width, nextSize.height);

I my testing I see the Copilot iframe which is hosting the SharePoint Copilot App resize when the appropriate message is send using above method.

[HarminderSethi]

Bert Jansen (@jansenbe) Yes, I have tested this function in one component. It works most of the time. In the few instances where autoSize still fails to trigger properly, doing a hard refresh on the Copilot page gets it working again.