[1]Firefox 149 is here, and although we've already talked about one of the big new features on the way, the release version has some others that will be very welcome.

We looked at the [2]new split view function a few weeks ago, along with the info on how to enable it in versions of Firefox back to 146 from last December. That's probably the most visible new feature, but we don't want to repeat ourselves, so if you missed it, go read that.

However, we did miss one handy little UI feature. When you're in split view, one pane is the active one: if you type into a box, that's where your text will go. In our testing on macOS and Linux, it's got a thin blue outline around the active pane. The other, inactive pane gets a tiny tab in its bottom right corner, which shows the page's base domain and its [3]favicon , followed by an ellipsis (the "…" symbol). Those three dots are a hamburger menu, and they have three handy and fairly self-explanatory functions for managing the split view: Separate Tabs, Reverse Tabs, and then after a separator, Close Both Tabs. The same options also appear in the address bar, where they're represented by a half-shaded rectangle.

[4]

Firefox 149 in split view – note that subtle little tab control at bottom right

Split view isn't the only visible new feature, though. Firefox now contains a free [5]built-in VPN . Mozilla is doing a progressive rollout of this feature, so it won't be available to everyone in all regions – notably, the Irish Sea wing of Vulture Towers doesn't have it yet. The Firefox VPN is not the same as [6]Mozilla's paid VPN , and the integrated one only affects web content that you're viewing in that instance of Firefox, so it's no use for internet-connected gaming and so on. Apparently the free VPN will offer 50 GB of traffic per month, which will be enough for occasional use but not for daily streaming.

An in-browser VPN can be a useful extra. To the recurring surprise of some commenters, this vulture tends to side with [7]XKCD 538 – and indeed [8]XKCD 1200 – when it comes to most of the security features that many techies idolize. We consider them pointless security theater, and for most purposes, so are VPNs. You don't need to "hide your IP" as many adverts proclaim: nobody cares. Where it is sometimes useful is bypassing other security features. A year ago, we [9]wrote about adding a Pi-hole to your home network, and we're still using it. A snag with a DNS-level ad-blocker, though, is that it's not easy to temporarily turn it off, for example, on sites that won't display unless you permit ads. An in-browser VPN bypasses this with one click. Yesterday, we wrote about claims that [10]Meta is sponsoring OS age verification legislation , and found we were blocked by the Meta-funded DCA pressure group. Once again, an in-browser VPN came in very handy.

[11]

We say "came in" because we do already have one – in Opera. Although the Norwegian company [12]sold its browser to a Chinese consortium a decade ago, the free Opera browser still exists, and we keep it around simply because it has a free in-browser VPN. Some of the original Opera team created the Vivaldi browser instead, which is [13]still very much around and [14]blissfully AI-free . Vivaldi also [15]added a free Proton VPN a year ago. Both of these offer unlimited traffic.

[16]

[17]

So this is not some industry-redefining innovation from Mozilla, but it's welcome all the same. A year ago, we removed all our vertical tab add-ons when [18]Firefox 136 built this in . Once we can use the Firefox VPN, we'll probably be removing another browser – certainly from those of our machines that are a little more pressed for disk space.

[19]Firefox taps Anthropic AI bug hunter, but rancid RAM still flipping bits

[20]Firefox 149 beta develops a split personality

[21]Firefox 148 adds master switch for browser bot bother

[22]Firefox makes AI optional, like it probably should have been all along

Firefox 149 also allows you to attach (and edit and remove) sticky notes to browser tabs. If you are such a taboholic that you sometimes lose track of why you left something open, we can see that this could be handy, while staunchly denying that we have such extreme tab management problems. We will allow that it is hypothetically possible that we did in the past, though.

Firefox's [23]mascot Kit is now much more visible, appearing on the first-run pages and on some error pages. It is not as interactive as [24]Chrome's dinosaur , but we have to admit that we didn't mind this as much in real life as we thought we would from the description.

The last visible tweak only affects Linux users, but they may welcome it anyway. Firefox now automatically uses XDG portals to use the file Load and Save dialogs provided by the underlying OS, rather than the standard Gtk3 ones. As the [25]Arch wiki describes , this has been an option since [26]Firefox 64 back in 2018 – the same version that [27]removed the built-in RSS reader . Mozilla giveth, and Mozilla taketh away (as [28]the Book of Mozilla might put it).

Opera GX comes to Linux too

In other Linux browser news, there's another sign, should you need it, that Linux continues to gain penetration among gamers. Opera's special edition of its browser aimed at this audience, [29]Opera GX , is [30]now available for Linux .

[31]

Opera GX 128 on Pop!_OS – a macho browser for big guys with (virtual) guns

It's not in the Snap Store or on Flathub just yet, but we used Firefox 149 on Pop!_OS 24.04 to visit the Opera GX site, and the Download button furnished us with a .deb package without further ado.

It's the Chromium-based Opera with a built-in ad blocker – which sounds useful – plus a rather aggressive dark theme with angular highlights and a choice of accent colors. Opera GX can integrate several social networks and chat systems into sidebars, and offers background music and keyboard sound effects (our [32]trusty IBM Model M will drown those out ). There are quite a lot of other bells and whistles too. We're not sure we really see the appeal, but then we're not the target demographic. The last new game The Reg FOSS desk bought was [33]Untitled Goose Game , and we're not very good at it.

[34]

We didn't have "running Windows games" on our bingo card for the Year of Linux on the Desktop, but it increasingly looks like that will be what does it. ®

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[1] https://www.firefox.com/en-US/firefox/149.0/releasenotes/

[2] https://www.theregister.com/2026/03/02/firefox_149_beta/

[3] https://www.w3schools.com/html/html_favicon.asp

[4] https://regmedia.co.uk/2026/03/25/firefox-149.jpg

[5] https://support.mozilla.org/en-US/kb/built-in-vpn

[6] https://www.mozilla.org/en-GB/products/vpn/

[7] https://xkcd.com/538/

[8] https://xkcd.com/1200/

[9] https://www.theregister.com/2025/03/08/pi_hole_6_flyby/

[10] https://www.theregister.com/2026/03/24/foss_age_verification/

[11] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_software/applications&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2acQUslVWcQUPqOjh0yG4jAAAAJM&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0

[12] https://www.theregister.com/2016/07/18/no_12bn_opera_buyout/

[13] https://www.theregister.com/2026/03/19/vivaldi_7_9/

[14] https://www.theregister.com/2026/01/29/vivaldi_release_ai/

[15] https://www.theregister.com/2025/03/27/vivaldi_proton_vpn/

[16] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_software/applications&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44acQUslVWcQUPqOjh0yG4jAAAAJM&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0

[17] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_software/applications&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=3&c=33acQUslVWcQUPqOjh0yG4jAAAAJM&t=ct%3Dns%26unitnum%3D3%26raptor%3Deagle%26pos%3Dmid%26test%3D0

[18] https://www.theregister.com/2025/03/04/firefox_136/

[19] https://www.theregister.com/2026/03/06/firefox_bugs_anthropic_ai/

[20] https://www.theregister.com/2026/03/02/firefox_149_beta/

[21] https://www.theregister.com/2026/02/25/firefox_tbird_148/

[22] https://www.theregister.com/2026/02/03/firefox_ai_kill_switch/

[23] https://blog.mozilla.org/en/firefox/meet-kit/

[24] https://www.theregister.com/2021/01/28/bork/

[25] https://wiki.archlinux.org/title/Firefox#XDG_Desktop_Portal_integration

[26] https://www.firefox.com/en-US/firefox/64.0/releasenotes/

[27] https://www.theregister.com/2018/10/13/mozilla_firefox_kills_rss/

[28] https://www.mozilla.org/en-US/book/

[29] https://www.opera.com/gx

[30] https://blogs.opera.com/news/2026/03/opera-gx-lands-on-linux/

[31] https://regmedia.co.uk/2026/03/25/opera-gx.jpg

[32] https://www.theregister.com/2021/12/03/mechanical_keyboard_asmr/

[33] https://www.theregister.com/2019/10/29/untitled_goose_game_rce/

[34] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_software/applications&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44acQUslVWcQUPqOjh0yG4jAAAAJM&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0

[35] https://whitepapers.theregister.com/