What is "monospace" in Chrome?

Question

I'm on Ubuntu 15.10 and use Chrome (47.0.2526.106). As I understand "monospace" is simply an instruction (as in not a specific font) to use the "system" monospaced font. In Chrome Settings the "Fixed-width font" is set to "monospace". Then in my Tweek Tool Fonts Monospace I've set Courier -- but what I see when a page (e.g. a simple error page) comes up is not Courier but something that resembles Ubuntu Mono, but not exactly. What font is Chrome using? Is it sending a font, or is it using something else on my system?

Answer 1

Type this url into your browser (chrome://settings/fonts) and see which font is set for "fixed width."