Previously, only when multirun option 're-use tab to run configuration' was used, the started configuration was pinned. Now, it seems that it is always pinned in IntelliJ 14 / Multirun 0.9.1.
Tabs would be pinned, unless 're-use tab to run configuration' is set. Going to update Multirun and see it works as expected. Please reopen if you still have the issue.
Previously, only when multirun option 're-use tab to run configuration' was used, the started configuration was pinned. Now, it seems that it is always pinned in IntelliJ 14 / Multirun 0.9.1.