Created attachment 102687 [details]
Heap dump GC root reference chain

While tracking down a leak of many closed projects in 101026-de2112c9e0f2, I found a complex leak in at least one case of the DataObject for the manifest.mf in a NbModuleProject (which indirectly holds the project for several valid reasons). Tracking down the reference chain for the DataObject, I found it held by some Java parser information associated with a WhereUsedQueryUI, ultimately held by the button listener on an NbDialog, i.e. the "Find Usages" dialog, which of course I had long since closed. I'm not sure exactly why this is being held, but the fact that a long-closed Dialog can be held in memory is a major problem. If there is no clear way to release the Dialog itself, then NB must at least remove all of its components and clear any fields which might link to module objects (buttonListener in this case).