info.magnolia.imaging.caching.CachingImageStreamerRepositoryTest#requestForSimilarUncachedImageOnlyGeneratesItOnce started to fail after I recreated the jobs. It doesn't seem to be random, nor an easy fix.

Stacktrace https://jenkins.magnolia-cms.com/job/modules/job/imaging/job/master/3/testReport/info.magnolia.imaging.caching/CachingImageStreamerRepositoryTest/requestForSimilarUncachedImageOnlyGeneratesItOnce/

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Did investigate and I guess I found the cause. The test reveals a possible race condition where a thread tries to fetch a generated cached image before the latter is properly stored in JCR (see also https://git.magnolia-cms.com/projects/MODULES/repos/imaging/browse/magnolia-imaging/src/main/java/info/magnolia/imaging/caching/CachingImageStreamer.java#187)