When you modify the raw data of a backend workflow's initialization request — using the "Modify Types" > "Edit raw data" option — your changes won't save if the raw data exceeds 10,000 characters. The editor may appear to save successfully, but the changes aren't written to your app's data. This limit exists to prevent app JSON from getting too large.
What you might notice
You edit a key name in the raw data and click save, but the change isn't there when you reopen "Modify Types"
The behavior only occurs when the initialization request body exceeds 10,000 characters — for example, when sending a base64-encoded image
The editor doesn't show an error, so it can look like the save worked
Workaround
Keep your initialization request body under 10,000 characters. If you're sending large payloads (like base64 images), consider passing a URL reference instead of the full encoded data.