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Prior to upgrading to Jetty12 for the first time, you should remove all use of the backchannel and update and distribute your metadata appropriately. You should NOT remove the backchannel properties from jetty-base\start.d\idp.ini at this stage (since you your existing jetty installation will still support the backchannel and expect the properties). Once the metadata has propagated you can upgrade to Jetty12.
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