Invalid content-type header when POSTing without a body

[andraz-kozelj]

I have checked the following:

• I have searched existing issues and found nothing related to my issue.

This bug is:

• making Bruno unusable for me
• slowing me down but I'm able to continue working
• annoying
• this feature was working in a previous version but is broken in the current release.

Bruno version

2.4.0

Operating System

macOS 26 beta 1

Describe the bug

I have a POST request, with a single "Accept" header and no body.

When I sent it towards the server, server produced an error that the Content-Type header was "application/x-www-form-urlencoded" even though nobody set this header.

cURL code produced was correct:
curl --request POST \ --url 'http://localhost:8189/rest/v1/fhir/$reindex' \ --header 'accept: */*' \ --header 'authorization: Bearer {{authToken}}'

Timeline request DID NOT SHOW the "Content-Type" header.

Network logs showed the "undefined" as Content-Type value.

I did intercept the traffic and this was actually sent, where Content-Type header "Content-Type: application/x-www-form-urlencoded" is obviously added.

• Seems that content displayed in timeline/network logs does not represent the actual content of the request
  and
• no Content-Type header defined actually produces a header with an unwanted value.

.bru file to reproduce the bug

No response

Screenshots/Live demo link

I have a POST request, with a single header and no body.

When I sent it towards the server, server produced an error that the Content-Type header was "application/x-www-form-urlencoded" even though nobody set this header.

cURL code produced was correct:
curl --request POST \ --url 'http://localhost:8189/rest/v1/fhir/$reindex' \ --header 'accept: */*' \ --header 'authorization: Bearer {{authToken}}'

Timeline request DID NOT SHOW the "Content-Type" header:

Network logs showed the "undefined" as Content-Type value:

I did intercept the traffic and this was actually sent, where Content-Type header is obviously added:

• Seems that content displayed in timeline/network logs does not represent the actual content of the request
  and
• no Content-Type header defined actually produces a header with an unwanted value.

[Its-treason]

I had a slightly similar issue a few weeks ago: #4428

The Timeline seems to be inaccurate in other cases too.

[anusree-bruno]

Thanks for raising this issue. The second part — “no Content-Type header defined actually produces a header with an unwanted value” — is being tracked separately here: issue #2323.

[andraz-kozelj]

Great.
I DID search the existing issues using keywords, but did not spot other linked issues. :(
Sorry for the hassle.