FeatherPad (by Pedram Pourang, a.k.a. Tsu Jan) is a lightweight Qt
plain-text editor for Linux.  It is independent of any desktop
environment.  Some of the features include:

  Drag-and-drop support, including tab detachment and attachment.
  X11 virtual desktop awareness
  (using tabs on current desktop but opening a new window on another).
  An optionally permanent search-bar with a different search
  entry for each tab.
  Instant highlighting of found matches when searching.
  A docked window for text replacement.
  Support for showing line numbers and jumping to a specific line.
  Optional selection highlighting.
  Automatic detection of text encoding as far as possible and
  optional saving with encoding.
  Syntax highlighting for common programming languages.
  Ability to open URLs with appropriate applications.
  Session management.
  Side-pane mode.
  Auto-saving.
  Spell checking with Hunspell.
  Printing.
  Text zooming.
  Appropriate but non-interrupting prompts.

FeatherPad was written in GTK+ at first,  then ported to Qt with more
features.

Note:

FeatherPad can be compiled without X11 support:

  NOX11=on ./featherpad.SlackBuild

the result will have all features except for virtual desktop awareness
and tab DND.  On Linux, FeatherPad works under Wayland and you don't
need to disable its X11 support for that.

To compile with X11 support:

  ./featherpad.Slackbuild
