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You must also override the version in start.d\idp-system.ini This allows the same jetty base to be deployed against Jetty 10 (which uses logback 1.3.x) and Jetty 11 (which uses logback 1.4.x)
The changes need to be made in the pom and start.d\idp-system.ini
SLF4J Version
Check the slf4j version in the top level pom for the jetty project and amend as appropriate
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You should also override the version in start.d\idp-system.ini This is defensive against Jetty 10 and Jetty 11 versions drifting apart
The change must be made in the pom as well as the start.d\idp-system.ini
start.d/idp.ini
Any changes to this file may need to be reflected in changes to the file idp.ini.rewrite.property.names and/or idp.ini.windows and/or idp-system.windows
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