Groovy4, FastStringService, V.206, etc

In case anyone else is still looking for a solution, I stumbled upon it being mentioned in the release notes of v.212. It is fixed in Collector version 36.200 or later, although I haven't tested this yet.

Fix is under "Setting groovy.v4.classloader.enable to true"
https://www.logicmonitor.com/release-notes/ea-collector-36-200

The Issue is listed under the v.212 release notes as a known issue.
https://www.logicmonitor.com/release-notes/v-212-release-notes