The AI web browser Dia is drawing inspiration from its predecessor, Arc, an earlier experiment in modernizing the web browsing experience that hailed from the startup known as The Browser Company. On Sunday, The Browser Company founder Josh Miller confirmed that the new AI browser will bring “Arc’s greatest hits” to Dia, including things like the sidebar mode, and combine that with AI-native features like memory and agents.
This explanation suggests that Dia, which has since been acquired by Atlassian for $610 million, could have an advantage in the AI browser race, as it builds on the company’s earlier learnings from developing Arc.
The latter was initially released in mid-2023 as a reinvention of the browser designed around the way people use the internet today. That included offering separate workspaces for work and personal browsing, support for pinned tabs, a Command Bar that worked like Apple’s Spotlight search, and a sidebar that included the search bar, tab list, user bookmarks, audio controls, and more.
However, Arc may have tried to push the envelope a bit too far: Miller later admitted that Arc was ultimately too complex for most people to adopt.
“Arc was simply too different, with too many new things to learn, for too little reward… On top of that, Arc lacked cohesion in both its core features and core values. It was experimental, that was part of its charm, but also its complexity,” Miller wrote in a blog post earlier this year, detailing the company’s decision to wind down Arc and open source it, and refocusing the company’s efforts on building Dia.
But Arc may not necessarily be a failure, even if it didn’t become a widely adopted consumer product. Instead, the browser gave the company a year-plus’ worth of insights into what sort of modern browser features resonate with users and which ones do not.
That could help the company get ahead when building out the feature set for Dia.
As Miller says in a post on X, “Dia’s architecture is much better for AI, speed, and security,” but it will introduce features that Arc fans loved, like the sidebar mode — which was just spotted in the company’s latest “early birds” release of Dia’s AI browser.
Already, Dia has added other features from Arc’s “greatest hits,” like turning Google Meet into a picture-in-picture player automatically when you switch tabs and custom keyboard shortcuts. Miller hinted that the company is exploring how to transition Arc’s Spaces — the distinct browsing areas with their own set of pinned tabs, favorites, themes, history, and cookies — to Dia. And he said Dia’s team is currently testing pinned tabs.
Miller additionally solicited feedback about other features to add, like swipeable profiles, and Arc Search-inspired updates for the Dia mobile app coming in 2026.
Plus, Miller notes, Dia will have less bloat and will be AI-native for things like memory and agents.
Following the acquisition by Atlassian, The Browser Company continues to operate independently. As a result, Miller said the company will be able to add more “browser basics,” referring to favorite Arc features, to the Dia browser. He also shared that Dia is developing deeper integrations with Atlassian’s Jira and other apps, like Linear, under its new owner.
