Yes, it is because you use your own menu version instead of the one coming with Freeplane 1.5.7_01 . You should replace <Entry name="JoinNodesAction" accelerator="control J"/> by <Entry builder="joinNodesActions" accelerator="control J"/>
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Yes, it is because you use your own menu version instead of the one coming with Freeplane 1.5.7_01 . You should replace <Entry name="JoinNodesAction" accelerator="control J"/> by <Entry builder="joinNodesActions" accelerator="control J"/>
Oh, I forgot I am using my own menu xml. Thank you!