BUG: Whiteboard image paste error during Post creation

[larssondenise]

Describe the bug
when I copy content, including 3 images, from one whiteboard and use it in post creation with whiteboard, it fails.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://alkem.io/building-alkemio-org/challenges/offsites/opportunities/2026teamoffsite/collaboration/draftokrsfeedback/whiteboards/wm36n
2. Copy the content including images
3. Click on post in another space
4. Add whiteboard as additional context
5. Paste the content in the whiteboard
6. Save and click post
7. See error

Additional context
Maybe related to images from another subspace?

Potential explanation from Anne in the error logs:

• You paste content with images directly into the whiteboard before posting → the whiteboard data package becomes too large → the WebSocket connection is dropped due to a ping timeout.
• If you open the whiteboard after posting and then paste the content, it works fine → the data is sent in smaller chunks via an established session.
• I think the solution here is to increase the maximum WebSocket message size.

Areas that will be affected
Optional, to be added by developer if relevant

Screenshots