Dia Browser vs SupaSidebar: Which Arc Replacement Is Right for You?
Dia Browser is Atlassian's AI-first Arc successor and ships an Arc-style sidebar, but it locks you into Dia. SupaSidebar brings Arc's sidebar workflow to whichever browser you already use - Safari, Chrome, Firefox, Brave, Zen, or Dia itself. Here's the honest comparison for Arc refugees.
What is Dia Browser?
Dia Browser
Atlassian's AI-first Arc successor
Dia is a Chromium-based macOS browser from The Browser Company, the same team behind Arc. Its headline pitch is AI-first browsing: a conversational assistant lives in the sidebar with Memory Search, Skills, and GPT-5 across queries. Productivity integrations rolled out fast through late 2025 (Gmail and Calendar in v1.1.0, Slack search in v1.6.0, Tab Groups in v1.9.0). Worth noting: Dia does not ship Arc's Spaces or its original Cmd+T command bar - the workflow is reorganized around profiles and the AI chat interface.
- Owner
- Atlassian (Oct 2025, $610M)
- First public release
- Oct 8, 2025 (v1.0.1)
- Engine
- Chromium
- Requires
- macOS 14+ · Apple Silicon
What is SupaSidebar?
SupaSidebar
Arc's sidebar workflow, on top of any browser
SupaSidebar is a macOS app, not a browser. It sits next to whichever browser you choose and adds the workflow Arc users miss: Spaces with iCloud sync, a Command Panel on Cmd+Ctrl+K, Air Traffic Control rules that route saves and links to the right space and browser, Live Tabs from every running browser, Smart Folders, Link Preview, and Window Tiling. For Arc refugees, it imports StorableSidebar.json directly in three clicks - Spaces, pinned tabs, and folders come over without manual rebuild.
- Type
- macOS sidebar app
- Browsers supported
- 25+ (Safari, Chrome, Arc, Dia, …)
- Sync
- iCloud, no account required
- Requires
- macOS 14+ · Intel or Apple Silicon
Dia Browser vs SupaSidebar: feature-by-feature
Verified against Dia's official changelog at diabrowser.com/changelog as of May 7, 2026. Dia ships features monthly - re-check before any major decision.
| Features | Dia Browser | SupaSidebar |
|---|---|---|
| Product type | Partial Standalone Chromium browser - replaces your existing browser | Yes Mac sidebar app that works alongside any browser |
| Sidebar Persistent sidebar for tabs, links, and apps | Yes Built-in vertical sidebar with switchable layouts (sidebar/top-bar toggle in v1.16.0, January 2026) | Yes Persistent sidebar across every supported browser |
| Vertical tabs | Yes Native vertical tabs in the sidebar layout | Yes Tabs surfaced in the sidebar across browsers |
| Pinned tabs | Yes Pinned tabs with theme-accent styling (refined in v1.4.0, November 2025) | Yes Pinned items in the sidebar - no per-space limit |
| Spaces (Arc-style) Project-based workspaces with their own pinned tabs and folders | No Uses profiles in separate windows - different mental model | Yes Spaces with iCloud sync, no account required |
| Command bar | Partial Replaced with AI chat interface - not Arc's Cmd+T command bar | Yes Command Panel (Cmd+Ctrl+K) with cross-browser search, 7 scopes, Ask AI mode |
| Native AI features | Yes AI is the central feature - conversational AI, Memory Search, Skills, GPT-5 across queries | Partial Ask AI mode inside Command Panel for sidebar-data queries |
| Productivity integrations | Yes Gmail and Google Calendar (v1.1.0, Oct 2025), Slack search (v1.6.0, Nov 2025), Google Sheets in Chat (v1.10.1, Dec 2025) | No Browser-agnostic, no built-in third-party integrations |
| Browser support | No Dia browser only | Yes 25+ browsers including Safari, Chrome, Firefox, Arc, Zen, Vivaldi, Brave, Helium, Dia |
| Live Tabs across browsers | No Sees Dia's own tabs only | Yes Open tabs from every running browser in one panel |
| Air Traffic Control (URL routing) | No Single-browser product - no cross-browser routing | Yes Routes saves and links to specific spaces, browsers, or profiles |
| Arc data import | No No Arc StorableSidebar.json import - manual recreation only | Yes 3-click direct import: Preferences > Import and Export > Arc > Import |
| iCloud / encrypted sync | Yes End-to-end encrypted Sync via Dia account | Yes iCloud sync with no account required |
| Mac hardware requirements | Partial macOS 14+ AND Apple Silicon required - no Intel support | Yes macOS 14+, universal binary - runs on Intel and Apple Silicon |
| Windows support | No Signup page only as of March 2026, not yet released | No Mac-only |
| Owner | Partial Atlassian (acquired The Browser Company October 2025 for $610M) | Yes Independent indie developer |
| Pricing | Partial Free tier plus Dia Pro at $20/month | Yes Free version available, paid tiers for power users |
| Overall | Atlassian-owned, AI-first | Best Choice |
Product type
Mac sidebar app that works alongside any browser
Standalone Chromium browser - replaces your existing browser
Sidebar
Persistent sidebar for tabs, links, and apps
Persistent sidebar across every supported browser
Built-in vertical sidebar with switchable layouts (sidebar/top-bar toggle in v1.16.0, January 2026)
Vertical tabs
Tabs surfaced in the sidebar across browsers
Native vertical tabs in the sidebar layout
Pinned tabs
Pinned items in the sidebar - no per-space limit
Pinned tabs with theme-accent styling (refined in v1.4.0, November 2025)
Spaces (Arc-style)
Project-based workspaces with their own pinned tabs and folders
Spaces with iCloud sync, no account required
Uses profiles in separate windows - different mental model
Command bar
Command Panel (Cmd+Ctrl+K) with cross-browser search, 7 scopes, Ask AI mode
Replaced with AI chat interface - not Arc's Cmd+T command bar
Native AI features
Ask AI mode inside Command Panel for sidebar-data queries
AI is the central feature - conversational AI, Memory Search, Skills, GPT-5 across queries
Productivity integrations
Browser-agnostic, no built-in third-party integrations
Gmail and Google Calendar (v1.1.0, Oct 2025), Slack search (v1.6.0, Nov 2025), Google Sheets in Chat (v1.10.1, Dec 2025)
Browser support
25+ browsers including Safari, Chrome, Firefox, Arc, Zen, Vivaldi, Brave, Helium, Dia
Dia browser only
Live Tabs across browsers
Open tabs from every running browser in one panel
Sees Dia's own tabs only
Air Traffic Control (URL routing)
Routes saves and links to specific spaces, browsers, or profiles
Single-browser product - no cross-browser routing
Arc data import
3-click direct import: Preferences > Import and Export > Arc > Import
No Arc StorableSidebar.json import - manual recreation only
iCloud / encrypted sync
iCloud sync with no account required
End-to-end encrypted Sync via Dia account
Mac hardware requirements
macOS 14+, universal binary - runs on Intel and Apple Silicon
macOS 14+ AND Apple Silicon required - no Intel support
Windows support
Mac-only
Signup page only as of March 2026, not yet released
Owner
Independent indie developer
Atlassian (acquired The Browser Company October 2025 for $610M)
Pricing
Free version available, paid tiers for power users
Free tier plus Dia Pro at $20/month
Overall
Why Arc refugees choose SupaSidebar over Dia
The sidebar workflow Arc taught us, without trading one browser lock-in for another.
Browser-independent by design
Dia is one browser. Switch away from Dia and your sidebar is gone. SupaSidebar layers on top of 25+ browsers including Safari, Chrome, Firefox, Brave, Zen, Vivaldi, and Dia itself - so the sidebar moves with you.
Runs on Intel Macs too
Dia is Apple-Silicon-only - if your Mac has an Intel chip, Dia won't launch. SupaSidebar ships a universal binary, so it runs on macOS 14+ on Intel and Apple Silicon alike. The hardware door isn't closed on you.
3-click Arc import
Dia has no direct Arc data import - you rebuild your structure by hand. SupaSidebar reads Arc's StorableSidebar.json directly: Preferences, Import and Export, pick Arc, click Import. Spaces, folders, and pinned tabs come over in seconds.
Indie, not enterprise
The Browser Company is now a subsidiary of Atlassian. Dia's roadmap will inevitably bend toward enterprise priorities. SupaSidebar is built and maintained by an independent developer focused on Arc refugees and macOS power users.
Who should pick which?
Three paths forward. The strongest setup runs Dia and SupaSidebar together.
Choose Dia Browser only
- AI is the central feature you want from a browser
- Slack, Notion, Gmail, and Calendar are your daily home
- You're okay with browser lock-in and trust Atlassian's roadmap
- You did not build your Arc workflow around Spaces
Choose SupaSidebar only
- You want Arc's sidebar without committing to one browser
- Safari, Chrome, Firefox, Brave, Zen, or Vivaldi is your daily browser
- You want direct 3-click Arc data import
- You want real Arc-style Spaces, not profiles in separate windows
Use both
- Dia handles AI-first browsing inside the page
- SupaSidebar adds Spaces, Command Panel, and cross-browser routing on top
- SupaSidebar treats Dia as one of its 27 supported browsers
- Your Arc data lives in SupaSidebar, so it survives any future browser change