The JETI plugin webresources defined in atlassian-plugin.xml are bound to the jira.admin context, that is the scripts are loaded on every admin page. They break syntax highlighting in other plugins, the Adaptavist Script Runner including.
Steps to reproduce:
install script runner
go to the script runner console, and try to enter script. it's pale.
If I disable the 'admin' webresource in the plugin administration, all is back to normal with script runner.
I did not try if JETI breaks the codemirror highlighting in scriptrunner workflow elements, worth checking too.