NPE pulling images through a docker proxy repository after upgrade to 3.19.0

We've seen a couple of reports now where users are getting NPE's pulling docker images after upgrading to 3.19.0.  The stack indicates the config field is null.    Re-saving the docker repository configuration resolves the problem.

2019-10-03 09:00:04,607+0000 WARN [qtp172103249-351] docker org.sonatype.nexus.repository.docker.internal.V2Handlers - Error: GET /v2/xxxx/yyyyy/manifests/0.0.16
java.lang.NullPointerException: null
at org.sonatype.nexus.repository.docker.internal.DockerProxyFacetImpl.getManifest(DockerProxyFacetImpl.java:921)
at org.sonatype.nexus.repository.docker.internal.DockerProxyFacetImpl.getCachedContent(DockerProxyFacetImpl.java:310)
at org.sonatype.nexus.repository.proxy.ProxyFacetSupport.maybeGetCachedContent(ProxyFacetSupport.java:369)
at org.sonatype.nexus.repository.proxy.ProxyFacetSupport.get(ProxyFacetSupport.java:229)
at org.sonatype.nexus.repository.proxy.ProxyHandler.handle(ProxyHandler.java:52)
at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
at org.sonatype.nexus.repository.view.handlers.LastDownloadedHandler.handle(LastDownloadedHandler.java:63)
at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
at org.sonatype.nexus.repository.storage.UnitOfWorkHandler.handle(UnitOfWorkHandler.java:39)
at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
at org.sonatype.nexus.repository.view.Context$proceed.call(Unknown Source)
at org.sonatype.nexus.repository.docker.internal.V2Handlers$_closure16.doCall(V2Handlers.groovy:273)
at sun.reflect.GeneratedMethodAccessor383.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:98)
at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:325)
at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:264)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1034)
at groovy.lang.Closure.call(Closure.java:418)
at org.codehaus.groovy.runtime.ConvertedClosure.invokeCustom(ConvertedClosure.java:54)
at org.codehaus.groovy.runtime.ConversionHandler.invoke(ConversionHandl