kovidgoyal/kitty · error

Terminal does not support reporting screen sizes in pixels,

Error message

Terminal does not support reporting screen sizes in pixels, use a terminal such as kitty, WezTerm, Konsole, etc. that does.

What it means

icat needs the terminal window size in pixels to place/scale images. The resolved screen size reports 0 pixels in width or height, meaning the terminal (or its queries) did not supply pixel dimensions.

Source

Thrown at kittens/icat/main.go:249

			return 1, err
		}
	}
	switch {
	case opts.ClearAll:
		cc := &graphics.GraphicsCommand{}
		cc.SetAction(graphics.GRT_action_delete).SetDelete(graphics.GRT_free_by_range).SetLeftEdge(0).SetTopEdge(math.MaxUint32)
		if err = cc.WriteWithPayloadTo(os.Stdout, nil); err != nil {
			return 1, err
		}
	case opts.Clear:
		cc := &graphics.GraphicsCommand{}
		cc.SetAction(graphics.GRT_action_delete).SetDelete(graphics.GRT_free_visible)
		if err = cc.WriteWithPayloadTo(os.Stdout, nil); err != nil {
			return 1, err
		}
	}
	if screen_size.Xpixel == 0 || screen_size.Ypixel == 0 {
		return 1, fmt.Errorf("Terminal does not support reporting screen sizes in pixels, use a terminal such as kitty, WezTerm, Konsole, etc. that does.")
	}

	items, err := process_dirs(args...)
	if err != nil {
		return 1, err
	}
	if opts.Place != "" && len(items) > 1 {
		return 1, fmt.Errorf("The --place option can only be used with a single image, not %d", len(items))
	}
	files_channel = make(chan input_arg, len(items))
	for i, ia := range items {
		ia.index = i
		files_channel <- ia
	}
	num_of_items = len(items)
	output_channel = make(chan *image_data, 1)
	keep_going = &atomic.Bool{}
	keep_going.Store(true)

View on GitHub (pinned to 6d5d0c4406)

Solutions

1. Run directly in kitty, WezTerm, or Konsole
2. If under tmux, set tmux to pass through the window size (terminal-overrides / latest tmux) or detach
3. Verify with kitty +kitten icat --print-window-size that a non-zero pixel size is reported

out, err := exec.Command("kitty","+kitten","icat","--print-window-size").Output()
// parse WxH; if either is 0, fall back to sixel/ascii or abort

When it happens

Trigger: Running kitten icat inside tmux/screen or a plain VT that answers TIOCGWINSZ with ws_xpixel/ws_ypixel = 0, or --use-window-size with pixel fields ending as 0 after some code path.

Common situations: tmux without proper TIOCGWINSZ passthrough; SSH into a legacy terminal; running under a non-graphics-protocol terminal multiplexer.

Related errors

• This terminal does not support the graphics protocol use a t
• Timed out waiting for a response from the terminal: %w
• Invalid value for --background: %w
• Invalid value for --z-index with error: %w
• unknown fit specification: %#v

AI-assisted analysis of kovidgoyal/kitty@6d5d0c4406 (2026-08-27). Data as JSON: /api/errors/b16265724a28f86a. Report an issue: GitHub.