Neither here nor powerline/fonts has any documentation of what codepoints are supposed to be provided with which glyphs by fonts. This makes it virtually impossible for font authors to add support.

Also, I’ve seen you use the PUA. Please register your codepoints with http://www.evertype.com/standards/csur/ so they don’t overlap with any other CSUR PUA assignments. (It’s easy, I got a couple ass

Change the default username color to something like blue (via variable, so it's changeable). Then, when user su's to root or logs in as root, change username color to RED. This would be a good visual warning that you might be doing something with root privs by mistake ...

So the _username function would check the euid, and if 0 set color to RED

First, thank you for tmux!

Second, when you write in the README:

When nesting tmux sessions via ssh or mosh, you could extend it to look like '(^|/)g?(view|vim|ssh|mosh?)(diff)?$', which makes this plugin work within the innermost tmux session and the vim sessions within that one.

Could you provide a complete, working example? Should we "extend", "add", or completely rewrite the single

The Pipfile lists many version pinned requirements.
IMHO requirements should ideally never be version pinned (only if really really required).
Please remove the version pinning, where not needed!
It's hard to do proper packaging with this (especially for distributions, that follow upstream closely, such as Arch Linux).

Some of the default bindings are incorrect in the README. For example, the previous/next window defaults are <prefix> C-[ and <prefix> C-], not <prefix> < and <prefix> >.

When I use the library to split window, I use win.cmd('split-window', '-h') which let me spend a lot of time.

At last, I suggest to use bash script instead of this library.

#!/usr/bin/env python3
# coding=utf-8
# author: thinkycx
# date: 2018-01-11
# Usage:
#    run several commands in tmux panel, every window have 4 panes
#    $ pip3 install libtmux
#    $ python tmux.py

A simple button on their profile or edit profile pages which lets them delete their own account will suffice :-)