Essential Firefox Tweaks

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I've been using Firefox as my primary web browser since Firefox Quantum was released as a beta (which is right around a year ago). It offered a nice refreshing UI after using Google Chrome for a few years. It also brought with it slightly faster rendering. Chrome might have caught back up but I honestly haven't looked back since making the switch.

Anyway, as much as I love using Firefox, there are a few essential tweaks I find myself making each time I reinstall the application. To apply these changes you'll need to first visit the following special page using your address bar:

about:config

Once you visit that page you can search for the values listed in this post and change them to the version on this page. If at any point you want to go back to the default value you can right click on the setting and choose Reset.

Address Bar Double Click Selection Behavior

This is probably the most annoying feature of the browser when I first migrated from Google Chrome. If you double click the URL in the location bar then the entire URL is selected. However, as a web developer, I often have the need to select only certain parts of the URL. For example, if a URL contains /xxx/yyy/zzz, and I double click one of the y values, then I expect only the yyy URL segment to be selected.

Make the following change to fix the double click selection behavior:

browser.urlbar.doubleClickSelectsAll = false

Prevent Ctrl+Scroll from Zooming

This one drives me nuts. I'm very frequently pressing the Ctrl key, and I'm very frequently scrolling. However, I very infrequently want to zoom the page (and I find pressing Ctrl = and Ctrl - easy enough). This problem is compounded by the fact that the browser supports scrolling momentum; scroll quickly using your trackpad, release your fingers, and tap Ctrl, and the screen is now frantically zooming and eating through CPU.

Holding the Ctrl key will no longer have any affect when you scroll once you make the following change:

mousewheel.with_control.action = 1

Prevent Dark OS Themes from affecting Form Controls

This is a bug that's been around for as long as Firefox has existed. When using a dark theme for your OS, Firefox will use the same theme colors for form controls on webpages. This often means you'll end up with black text on black background. This change instructs Firefox to use a popular light theme named Adwaita.

When you open about:config, you'll need to actually create a new entry, not modify an existing one. Create a new entry of type string, and set the key and value to the following:

widget.content.gtk-theme-override = Adwaita:light

Unfortunately, you'll need to set this value again after Firefox upgrades.

Disable Backspace from Going Back

This is probably the worst browser feature ever created and is triggered like so: You're busy writing your thesis in a large text box. Seven hours later you're ready to submit. You press tab to jump to the next field where you go to delete a superfluous character. You tap backspace and, well, turns out the focus switched to a small hyperlink the website author stuck between fields. The backspace keypress just took you to the previous page and your life's work is now lost.

The following change will prevent any special Backspace behavior:

browser.backspace_action = 2

Disable Pocket

Pocket represents some sort of goofy business idea that Mozilla had and is still paying for. It's an invasive integration into the browser, polluting both precious toolbar and context menu real estate.

Make the following change to disable Pocket support:

extensions.pocket.enabled = false

Cleanup New Tab Screen

When creating a new tab I really only care about quickly painting the screen. I'm always either going to paste in a URL or manually type a search query. By default the screen shows a bunch of recommended sites and recently visited sites, which I've never interacted with.

Make the following changes to simplify your new tab screen:

browser.newtabpage.activity-stream.feeds.section.highlights = false
browser.newtabpage.activity-stream.feeds.section.topstories = false
browser.newtabpage.activity-stream.feeds.snippets = false
browser.newtabpage.activity-stream.feeds.topsites = false

Disable Warn on Close Multiple Tabs

When I have a tab that's important, something that I really want to stick around, I'll right click on it and Pin the tab. This will keep the tab around even when I restart the browser (or if my computer crashes). Any other tabs I treat as being ephemeral.

Make the following change to prevent the browser from prompting you to exit when multiple unpinned tabs are open:

browser.tabs.warnOnClose = false
Thomas Hunter II Avatar

Thomas has contributed to dozens of enterprise Node.js services and has worked for a company dedicated to securing Node.js. He has spoken at several conferences on Node.js and JavaScript and is an O'Reilly published author.