Awesome replacement for IDEA's 'Show directory in editor tabs for non-unique filenames'. If you have same named files in different directories this plugin will allow you to have directory names added to tab labels. It only shows path differences so if you have "blog/controllers/index" and "news/controllers/index" it will add either [blog] or [news]. In setting tab 'Tabdir' you can control how prefixes will be formatted.
Per-project configuration allow specify different formatting rules for each directory in project. To enable per-project configuration enable "Use per project configuration" checkbox(see screenshot №3) and reopen settings window(need close with Ok or Apply buttons). After this you will find 'Tabdir' configuration in project section(screenshot №4) in which different configurations can be specified.Note: that you should turn off IDE Settings → Editor tabs → Show directory in editor tabs for non-unique filenames.