Waterfox 43.0 is now available to download for both Windows and Mac, bringing Waterfox up-to-date with Firefox release schedule.

What’s new in Waterfox 43.0.1?

  • Fixed various crashes with less aggressive optimisation flags (Removal of -Qprec-div- -Qip -Qopt-prefetch)

What’s new in Waterfox 43.0?


  • Based on 43.0.3
  • Fixed UI malformation caused by Bug 1157984
  • Enabled aggressive optimisation flags (-O3 -Qprec-div- -Qip -Qopt-prefetch -Qparallel -QaxCORE-AVX2,CORE-AVX-I,AVX,SSE4.2,SSE4.1,SSSE3 -arch:SSE3), which should bring performance back up to par!
  • Updated enabled HTML5 features
  • Added Disconnect.me and Ecosia search engines to the search engine list
  • Full support for Windows XP (including WebGL, may have to disable Hardware Acceleration)


  • Removal of 64-Bit NPAPI whitelist
  • Removal of signed extension requirement
  • Removal of Encrypted Media Extensions (DRM)
  • Removal of all Mozilla Data Reporting services (properly)


  • Fixed low resolution icons
  • Waterfox registry entries to not use the same as Firefox (Windows Only)
  • Automatic updates for Mac now work!

Other News

Very sorry for the late release on this one everybody. There were 2 breaking bugs that took me weeks to find and patch through the holiday season. One bug was where Waterfox would immediately exit upon starting up and the other was a malformed UI due to the -O3 flag. As usual, Waterfox automatic updates are delayed a bit to give time for them to be put across the whole CDN (takes up to 24 hours).

Firefox 64-bit for Windows is now available. What is the future of Waterfox?

This was asked in the Waterfox subreddit and I answered it. To sum it up: This doesn’t change anything for Waterfox. What I said in reply:

To carry it on. Intel’s C++ compiler still generates faster code than Visual C++ does and on powerful systems it makes a big difference. For example on my laptop with an i7-4720HQ, Waterfox 40.1.0 runs about ~20% faster in the JetStream (successor to SunSpider) benchmark compared to Firefox 42.0 64-Bit (and Waterfox’ main focus is speed ;) ). Once I get WF43.0 all finished up, I’ll make sure to put some benchmarks together and hopefully get some users to test as well.

But also there are other things:

A lot of features lie dormant in Firefox, either due to being forgotten or just leaving it for later. This makes sense, as Mozilla have other things to prioritize. But I don’t really, so I can enable these features (mostly talking about HTML5 features that work here). Some things Mozilla won’t implement, such as support for WebP images, Waterfox has implemented. Also as another example, back before Firefox for Mac had support for MP4 files, Waterfox implemented support for them utilising GStreamer (Mozilla wanted a native approach). And that was fine, but until that happened WF offered users an alternative while waiting for it. A lot of new Firefox “features” are against what Mozilla are about, such as integrating Pocket or the inclusion of HTML5 EME. Waterfox doesn’t include either and won’t (unless users really want them). I’m going to go through and strip out things such as this. Quite a few things aren’t on Mozilla’s list - such as updating 3rd party libraries very quickly (took a while for ICU to get updated to 55.1 from 52.1) for example. It’s not their fault either, if it works and they’ve got higher priority bugs to fix, it makes sense for things like that to fall behind. This leaves me to be able to go and update such things.

I knew Mozilla were bound to release a 64-Bit Firefox. That goes without saying. But that’s why back in 2012 I switched from just making 64-Bit Firefox builds (which took almost no effort) to making fast 64-Bit Firefox builds, and it’s something I hope to continue to do!

Waterfox will also most likely carry on using XUL after Mozilla deprecate it and I’ll hopefully carry on maintaining it properly (while also including features Mozilla bring in). This could be very hard to do though, so we’ll have to see.

If you’re keen on still helping out and making the world a better place, you should check out Ecosia. It’s available in the search engine list and plants trees with the revenue it makes!

Website Updates

The website will have a new Features page in the coming days. This makes it easy for you to keep track of what makes Waterfox different to Firefox (such as no proprietary software inclusions, more HTML5 features enabled, 64-Bit XP support and more) and should help you convince your friends to use Waterfox as well ;-)

As always, head to the Downloads page for the latest versions! (Language packs update coming tomorrow as well).