Version 8.5.x (June 2018 onwards) of the Apache Tomcat servlet container. Use only if your question is specifically related to features of this version.
Tomcat released on 2018-06-25:
The Apache Tomcat Project is proud to announce the release of version 8.5.32 of Apache Tomcat. Apache Tomcat 8.5.x is intended to replace 8.0.x and includes new features pulled forward from Tomcat 9.0.x.
Tomcat 8.5 is designed to run on Java SE 7 and later.
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The Apache Tomcat team announces that support for Apache Tomcat 8.0.x will end on 30 June 2018. 8.5.x is not affected by this announcement.