ChromeOS Terminal

In the terminal:

1. Use the keyboard shortcut CTRL + SHIFT + P
2. Scroll down to "Custom CSS (Inline Text)".
3. Copy & paste the following:

@font-face{
    font-family: 'Fira Code';
    src: url('https://raw.githubusercontent.com/tonsky/FiraCode/master/distr/eot/FiraCode-Regular.eot') format('embedded-opentype'),
         url('https://raw.githubusercontent.com/tonsky/FiraCode/master/distr/woff2/FiraCode-Regular.woff2') format('woff2'),
         url('https://raw.githubusercontent.com/tonsky/FiraCode/master/distr/woff/FiraCode-Regular.woff') format('woff'),
         url('https://raw.githubusercontent.com/tonsky/FiraCode/master/distr/ttf/FiraCode-Regular.ttf') format('truetype');
    font-weight: normal;
    font-style: normal;
}

* {
    -webkit-font-feature-settings: "liga" on, "calt" on;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    font-family: 'Fira Code';
}

4. Restart your terminals