Add possibility to hide/disable "close tab" button

Add ability to show indentation lines

Add bookmarks support

Make Ctrl + mouse scroll wheel increase / decrease coding font size (zoom in and out)

Ctrl + Shift + D should duplicate not only current line, but current selection if available

Make drag'n drop of some filetypes into editing area work under Linux

Change cursor shape within editing area from "pointer" to "text"

Add ability to show/hide word wrapping column