New trinket plugin for enable 'Open With' for files in project view. It usefull for some development, when you need, for example, open XML file but as Plain text (right click, Open With->Text files Editor). This also can be used for unassigned extensions in project. Files shown as 'Unknow' also can be opened by 'Open with' in any Lanaguage editor supported by IDEA.
I'm used it then i'm need to disable Language and open file as plain text. Or then i need to open Unknown file in seleted editor.
Plugin is available via Plugin Manager since 5231 build.