Global header value changes not saved when editing via workspace header viewer

When I open the global workspace headers through the “view” button and modify a header value (e.g., changing the HMAC encoding from Base64 to Hex), clicking save does not persist the change. The value silently reverts to its previous state on the next request.

Workaround: Editing the same header through the global header modification shortcut does persist correctly.

Steps to reproduce:

1. Create a global workspace header with an hmac.sha256(…) template function
2. Open the header via the workspace header viewer
3. Change the encoding value (e.g., Base64 → Hex)
4. Click save
5. Observe the value reverts to the previous encoding on the next request

Expected: The modified value should persist after saving.

Actual: The value silently reverts, giving no indication that the save failed.

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Another possibility is to disable the save button in read-only mode.