Worked stated on branch https://github.com/xwiki/xwiki-platform/commits/XWIKI-21211

Initial commit: https://github.com/xwiki/xwiki-platform/commit/3cd58fa246bea5221f992733cd9202b2b37ca6e6

Problems remaining:

• Duplicate container resource file warnings

  2024-01-09 11:37:31.127:WARN :oejew.MetaData:main: Duplicate Container Resource file:///Users/vmassol/dev/xwiki/xwiki-platform/xwiki-platform-distribution/xwiki-platform-distribution-flavor/xwiki-platform-distribution-flavor-jetty-hsqldb/target/xwiki-platform-distribution-flavor-jetty-hsqldb-16.0.0-SNAPSHOT/jetty/lib/jetty-servlet-api-4.0.6.jar
  2024-01-09 11:37:31.467:WARN :oejew.MetaData:main: Duplicate Container Resource file:///Users/vmassol/dev/xwiki/xwiki-platform/xwiki-platform-distribution/xwiki-platform-distribution-flavor/xwiki-platform-distribution-flavor-jetty-hsqldb/target/xwiki-platform-distribution-flavor-jetty-hsqldb-16.0.0-SNAPSHOT/jetty/lib/jetty-servlet-api-4.0.6.jar
  

• Logging config error

  SLF4J(E): A service provider failed to instantiate:
  org.slf4j.spi.SLF4JServiceProvider: Provider org.eclipse.jetty.logging.JettyLoggingServiceProvider not found

• NPE stack trace on the home page when not logged in. Probably caused by a null header set at https://github.com/xwiki/xwiki-platform/blob/master/xwiki-platform-core/xwiki-platform-rest/xwiki-platform-rest-server/src/main/java/org/xwiki/rest/internal/XWikiFilter.java#L103C13-L103C102 (not related to jetty 12 but the jetty code has changed 6 months ago to show a stack trace when this happens, see https://github.com/jetty/jetty.project/commit/660ba4bbe5d627554c9ce75803acd994538e1a80#diff-9d530518f578f0d9376f1d0b6474c16fbf2b1b9e24d7ebf898ad4e273fcdcb1dL594-R838 (you need to load the HttpFields.java changes)