Collapsed methods expands after IDE restart

I fold (collapse) some method in Android project i开发者_如何转开发n IntelliJ IDEA either via plus sign or via "right click->Folding->Collapse". I close IntelliJ. After I reopen the IDE, the methods are unfolded (expanded) again.

Is there a way to solve this? It this IDE's bug or I can fix this in IDE's properties?

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Folding of individual methods is not saved. The folding settings can be found here: File --> Settings --> Editor --> Code Folding