I stopped using Firefox forks and made regular Firefox do everything they did

Published Oct 25, 2026, 11:01 AM EDT Anurag is an experienced journalist and author who’s been covering tech for the past 5 years, with a focus on Windows, Android, and Apple. He’s written for sites like Android Police, Neowin, Dexerto, and MakeTechEasier. Anurag’s always pumped about tech and loves getting his hands on the latest gadgets. When he's not procrastinating, you’ll probably find him catching the newest movies in theaters or scrolling through Twitter from his bed. I’ve been a long-term Zen user. It’s a Firefox fork that puts more thought into tab management and the interface while keeping the same Gecko engine. I liked Zen because it offered an experience very similar to Arc (RIP), while letting me stick with a non-Chromium browser. You basically get all the goodness of Firefox with a more polished interface. There are plenty of other forks that offer their own take on a better Firefox, and I’ve tried my fair share of them. But I’ve now ditched all of them and returned to regular Firefox. The features that made me start using many forks are now available through a combination of built-in tools, extensions, and interface customization. Sidebery gives my tabs proper organization Zen’s workspaces are one of the reasons I’ve enjoyed using it. Once you get used to keeping different tasks in their own spaces, going back to a single strip of tabs is limiting. Firefox has extensions that offer similar organization, and Sidebery goes further by letting you arrange tabs into a tree. Sidebery puts your tabs in a sidebar with separate panels that you can name and organize. You could have one for work, another for personal browsing, and a third for whatever you’re researching. Each panel holds its own collection of tabs, so switching tasks doesn’t require sorting through everything else you have open. This covers much of what I want from workspaces without needing a separate browser. The tree structure is particularly useful for research. When you open links from a page in new tabs, Sidebery can place them beneath that page as children. If you’re reading about a self-hosted application, its documentation, GitHub repository, and installation guides can sit together under the original tab. You can collapse that branch when you’re working on something else and expand it when you need those pages again. You can also drag tabs around to adjust the structure yourself. There’s also a snapshots feature that saves information about your open tabs and windows. It’s a useful addition when you want to preserve a collection of pages without bookmarking each one individually. To set it up, install Sidebery from Firefox Add-ons, open it in the sidebar, and create your panels through its settings. You can explore the more detailed controls later; panels and nested tabs already give you plenty to work with. Firefox already has native vertical tabs You don’t need Sidebery just to move your tabs to the side of the window. Regular Firefox now has native vertical tabs, which cover one of the most visible reasons to try a browser like Zen. If your main complaint is that horizontal tabs become impossible to read once you have enough open, the built-in option is worth trying before installing anything else. The extra room for page titles makes a difference when you’re looking through several pages from the same website. Favicons won’t help you distinguish between five GitHub repositories or a handful of articles from the same publication. With tabs arranged vertically, you have more of each title to work with. You can keep the sidebar expanded to show those titles or collapse it when you want more room for the page. Firefox’s tab groups also work with vertical tabs, so you can gather related pages under a named group and collapse it when you’re finished with that task. For a few collections of work and personal tabs, that’s enough organization without another extension to configure. You still have everything in the same browser window, with controls that are part of Firefox itself. To enable native vertical tabs, right-click the Firefox toolbar or tab strip and select Turn on Vertical Tabs. You can then right-click a tab to add it to a group. I can change Firefox’s appearance myself Customize the interface without switching browsers Zen’s interface was a big part of its appeal to me, and installing a tab extension doesn’t automatically give regular Firefox the same polish. Fortunately, Firefox gives you room to change those as well. You can start by right-clicking the toolbar and selecting Customize Toolbar. From there, you can move the controls you use frequently and remove buttons you don’t need. Themes let you change the browser’s colors, which helps bring the sidebar and the rest of the window closer together visually. For bigger changes, Firefox supports interface customization through a file called userChrome.css. It lets you change how parts of the browser look, including their spacing, visibility, and placement. You don’t have to write the CSS yourself, either, since community projects provide ready-made themes with their own installation instructions. FF Ultima is one option worth exploring, particularly if you’re using Sidebery. It includes support for integrating the extension into its interface, giving the sidebar a more consistent appearance alongside the browser’s other controls. I’m happy sticking with regular Firefox I still like what Zen does, but I don’t need to keep using it just because I prefer its interface to Firefox’s default layout. I’m willing to do a little configuration to get the browser I want, and regular Firefox now covers enough of my needs that I have no reason to switch back.