Eclipse does not show all existing run configurations

Question

I use the Java Perspective of Eclipse Mars.2 and not all run configurations are shown in the tree view (see figure below).

There is a run configuration called "ELoadGUI (2)". If I try to rename it to "ELoadGUI" ... I get a hint that the run configuration "ELoadGUI" already exists.

However, that "already existing" run configuration is not shown in the tree.

How can I show all existing run configurations?

Answer 1

#Facepalm: The filter options where responsible for that behavior: