What did you do?

The new OTLP receiver translation strategy NoUTF8EscapingWithSuffixes is documented as "preserves all special characters like dots", but instead it does escape certain characters in metric names when adding of metric suffixes is enabled.

What did you expect to see?

I expect that the NoUTF8EscapingWithSuffixes translation strategy corresponds to the model.UTF8Validation name validation scheme, in allowing all valid UTF-8 characters, for both metric and label names.

What did you see instead? Under which circumstances?

Let's say you have an OTel gauge with the name "metric.+name+" and unit "°C". The translation logic, when adding of metric suffixes is enabled, will currently produce the Prometheus metric name "metric.name+°C", while the correct translation should instead be "metric.+name+_°C".

I've tested #15440, but it only partially remedies the above case.

System information

No response

Prometheus version

v0.300.0-237-gb407c2930

Prometheus configuration file

No response

Alertmanager version

No response

Alertmanager configuration file

No response

Logs

No response