[DiapDealer]

It actually used to work that way (I don't remember exactly what triggered it) on Windows in the past (with any resource in Book Browser that was allowed to be renamed). I don't know if we disabled it somehow, or if it's down to a Qt change. But regardless, there's only so many signals we can work with. Double-clicking a file in Book Browser opens the file in a new tab (on Windows anyway), and I don't think having the default platform tree-rename editor fire with each and every single-click on a File in the Book Browser would please anyone, so just what mouse event would the OP have us associate with this quicker rename request?

Making the Book Browser behave the same as a platform's standard file browser is not something we're really striving for. Especially now that the Book Browser tree view is a virtual representation of the collection of files in an epub and not a physical one.