Here is a screenshot of my terminal when I open tmux:

Note: Here, my shell displays my username@hostname but it does not display it in colors  🙁

To make tmux read your bash colors, edit your tmux configuration file:

vim ~/.tmux.conf

Add the following line to the tmux config file:

set -g default-terminal "screen-256color"

Exit and save the file. Close and re-open tmux.

Now, when you open tmux you should be able to get your regular bash prompt colors. Here is a screenshot after re-opening tmux:

Hope this helps! Cheers!

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