HTTP allows content-types to have priorities assigned via the attribute "qs", and the spec allows a value between 0 and 1. We had to remove it for when upgrading to Jersey 2.27.
The documentation mentioned the fix was for web browsers. I checked the web browsers and they all continued to work, and the integration tests passed, so went ahead and merged.
However, turns out the failure was a bit random. We need to deprioritize text/plain