[not reproducible] chimera viewer pane didn't open after selecting structures

Noticed this exception whilst testing new query-history drop down menu for searching PDBe. I had lots of windows open in Jalview before.. not been able to reproduce the message:
ERROR - Couldn't open Chimera viewer!
java.lang.IllegalArgumentException: illegal component position
at java.awt.Container.addImpl(Container.java:1087)
at javax.swing.JLayeredPane.addImpl(JLayeredPane.java:231)
at javax.swing.JDesktopPane.addImpl(JDesktopPane.java:484)
at java.awt.Container.add(Container.java:417)
at jalview.gui.Desktop.addInternalFrame(Desktop.java:931)
at jalview.gui.Desktop.addInternalFrame(Desktop.java:752)
at jalview.gui.ChimeraViewFrame.initChimera(ChimeraViewFrame.java:382)
at jalview.gui.ChimeraViewFrame.run(ChimeraViewFrame.java:565)
at java.lang.Thread.run(Thread.java:745)
WARN - Could not open /var/folders/km/m8_86nbd4bbcpd5s2h8xqtk4_kj190/T/jalview4073998711039045910.cif
WARN : ext.edu.ucsf.rbvi.strucviz2.ChimeraManager - Could not open /var/folders/km/m8_86nbd4bbcpd5s2h8xqtk4_kj190/T/jalview4073998711039045910.cif

not sure if the warnings are relevant or not. Query to PDBe was 'torda', and I picked 5cx7.