Überzug++ is a C++ command line utility which allows to draw images
on terminals by using child windows or using sixel on supported
terminals. (This is a drop-in replacement for the now defunct
ueberzug project.)

Advantages over w3mimgdisplay and ueberzug:

- support for wayland (sway only)
- no race conditions as a new window is created to display images
- "expose" events will be processed, so that images will be
redrawn when switching workspaces
- tmux support on X11
- terminals without the WINDOWID environment variable are supported
- chars are used as position and size unit
- A lot of image formats are supported (through opencv and libvips)
- GIF and animated WEBP support on X11 and Sixel
- Resized images are cached for faster viewing