Steps to Reproduce

unzip the jars provided in the binary download packages and compare jar versions

Current Result

• gson.jar 2.3.1
• closure-compiler.jar v20200426
• which contains gson classes of version 2.7

Expected Result

A) only one implementation version of gson to avoid class loading/version conflicts
or
B) remove the optional closure compiler completely or into a subfolder it's an optional dependency
or
C) use closure-compiler-unshaded.jar and eliminate jar conflicts before bundling the download packages

Debug Information

the maven dependencies use the closure-compiler-unshaded.jar to avoid duplicate dependencies

Workaround

RECOMMENDED: use a dependency management tool such as maven or gradle

(if maven/gradle are not available): don't add (the optional) closure-compiler.jar to a project