Firefox 57 - Enable U2F

I really love the new Firefox. I have the impression it runs much smoother, especially with some bloated sites. I also guess it won't take too long until webdesigners are making their websites even more bloaty, so that in some months from now we will be at the same time again.
Let's see how many new JS frameworks it will trigger 😉

Jokes aside, with Firefox 57 now disabling all legacy add-ons I was wondering, if U2F is finally supported. Turns out, it is, but you have first to enable it manually.

It's hidden in the about:config preferences. Search for webauth and enable the following options:

  • security.webauth.u2f
  • security.webauth.webauthn_enable_softtoken

Here you can see a Screenshot, in order to do so.

The Yubikey-demo page swollows the Yubikey - Seems to work!

Update - On Arch Linux it was not working out of the box. I had to follow the instructions from

1. Enable udev rules for Yubikey

2.Install U2F modules


Firefox (and Chrome) are eating your SSD

The "restore interval" write function of Firefox (and also Chrome) produces a lot of writings over the day, according to this page.

Firefox is eating your SSD – here is how to fix it


Go to about:config and search for the value browser.sessionstore.interval

This is by default set to 15 seconds and causes the hige integrated written bits over a day - more 10th Gibibytes (GiB) per day. The time is given in millseconds.

I've set it to 30 minutes, so in my configuration

browser.sessionstore.interval = 1800000


Restart the browser and that's it 🙂

Firefox 48 with multiprocess support

Firefox 48 was released on August 2. It has some quite good features, including a new experimental multiprocess support. Some of the most exciting new features are the following

Details can be found on the release notes.

Enable multiprocess support

If you got to about:support, you can see, if you have been selected for Multiprocess support - Check for Multiprocess Window 0/1 (Disabled)

Checking for Multiprocess support in Firefox 48
Checking for Multiprocess support in Firefox 48

You do this at OWN RISK. This is not encouraged! (Especially if you use extensions!)

But I did it too on my Arch Linux Desktop and on my Ubuntu 14.04 Desktop.

Within about:config create a new boolean browser.tabs.remote.force-enable with the value true.