JabRef version

Latest development branch build (please note build date below)

Operating system

Windows

Details on version and operating system

No response

Checked with the latest development build (copy version output from About dialog)

• I made a backup of my libraries before testing the latest development version.
• I have tested the latest development version and the problem persists

Steps to reproduce the behaviour

1. Enable "HIde Tab when single library is present"
2. Open two libraries
3. Select "Close all" (right click on
4. Group tree still shows the entries of the last opened library

Appendix

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