We are currently using a relatively old version of Apache Solr.
I will try upgrading to the latest stable version, 8.6.3
Deprecate embedded Solr server
solr support of embedded server conflicts with Guava upgrade
Document that Java 8 is needed for Oak 1.4 and 1.6 in the future
Make it possible to update Guava
javadoc errors in oak 1.6