Synchronous behaviour for express error

[nitinet]

Summary

Proposed change:

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Closes # .

Checklist

I've completed the checklist below to ensure I didn't forget anything. This makes reviewing this PR as easy as possible for the maintainers. And it gets this change released as soon as possible.

• Proposed change helps towards purpose of this project.
• Documentation is added / updated to describe proposed change.
• Tests are added / updated to cover proposed change.
• Changelog has an entry for proposed change (if user-facing fix or feature).

(Tick of items by replacing [ ] by [x])

[vecmezoni]

Could you please supply a test for that?