On upgrade to 18.1.7 of Eclipse plugin, double click and View Element in Element View no longer works for environments that are not entry environments.
(e.g. DEV environments work ok; Mapped PROD environments do not).
Message from the log:
Listing Types Finished with Warning (RC=0004)
Unknown element type: COBOLMVS
Release : 18.1
Component : CA Endevor Software Change Manager
CA Endevor SCM Plug-in for Eclipse 18.1.7.202010081014
Upgrade Endevor plugin 18.1.8 solved the issue.