Unable to propagate UserId via MDC

[MatthiasMpo]

Expected behavior

When I insert the userId into the logging context via MDC, I would expect that it would be mapped correctly.

Actual behavior

UserId is only visible as custom properties.

To Reproduce

// does not work
MDC.put("enduser.id", userId)
// does work
Span.current().setAttribute("enduser.id", userId)

System information

Please provide the following information:

• SDK Version: 3.4.15
• OS type and version: Windows
• Application Server type and version (if applicable):
• Using spring-boot? Yes (3.1.2)
• Additional relevant libraries (with version, if applicable):