If you would like the mobile-friendly versions of sites to load by default, there are two ways to do this:
#[https://addons.mozilla.org/en-US/firefox/addon/user-agent-switcher-revived/ Install the User Agent switcher] extension - this allows for easy switching between different user agents.
#A more permanent option is to go into <code>about:config</code>, right click, New → String,
Enter <code>general.useragent.override</code> and then type in the user agent you wish to use.
== Upcoming versions ==
With upcoming versions (> 55) we will be able to use the multi-touch zoom extension to get fluid zooming.