Hide or show titles in i3wm windows depending on if the Workspace has more than one window. Requires [i3ipc-python](https://github.com/acrisci/i3ipc-python) to be installed.

i3-smarttitles.py

#!/usr/bin/env python

import i3ipc

# Create the Connection object that can be used to send commands and subscribe
# to events.
i3 = i3ipc.Connection()

def change_titles(windows):
    if len(windows) > 1:
        command = 'border normal'
    else:
        command = 'border pixel 1'

    for window in windows:
        window.command(command)

def on_window(self, e):
    focused = i3.get_tree().find_focused()
    change_titles(focused.workspace().leaves())

# Subscribe to events
i3.on('window', on_window)

# Start the main loop and wait for events to come in.
i3.main()

You should add this to your ~/.i3/config so that it is executed always at startup by adding exec --no-startup-id /path/to/i3-smarttitles.py