[Feature]: Multiple Spaces for organizing projects and threads (Arc/Zen-style) #2293

Before submitting

• I searched existing issues and did not find a duplicate.
• I am describing a concrete problem or use case, not just a vague idea.

Area

apps/desktop

Problem or use case

When working across many projects (work, side projects, open-source contributions, experiments), the sidebar becomes a long flat list of projects and threads with no way to separate them by context. Switching between a work project and a side project means scrolling through an undifferentiated list, which slows navigation and adds cognitive overhead — especially once you have 10+ projects open.

Proposed solution

Introduce Spaces — named, switchable groups that each contain their own set of projects and threads. Similar to how Arc Browser and Zen Browser handle this:

• A Space switcher in the sidebar (e.g. vertical icon strip or tabs at the top) to move between spaces like "Work", "Side Projects", "OSS", etc.
• Each Space shows only its own projects and threads, keeping the sidebar clean and focused.
• Users can create, rename, reorder, and delete Spaces.
• Projects can be moved or assigned to a Space (drag-and-drop or right-click context menu).
• A keyboard shortcut to cycle between Spaces (e.g. Cmd+1/Cmd+2 or Ctrl+1/Ctrl+2).
• New projects default to the currently active Space.

Why this matters

Power users and professional developers often juggle many projects across different contexts (employer work, freelance, personal). Without a way to group them, the sidebar becomes cluttered and hard to navigate. Spaces would let users maintain focus within a context and switch cleanly between them — a UX pattern that Arc and Zen have proven works well for exactly this kind of multi-context workflow.

Smallest useful scope

Named Spaces that each hold their own project list, with a simple switcher in the sidebar to move between them. No need for per-Space theming, profiles, or separate provider configs in a first pass — just scoped project/thread visibility.

Alternatives considered

• Collapsible folders/groups in the sidebar — lighter weight but doesn't provide the same clean context-switching UX; the sidebar still shows everything at once.
• Multiple windows — related issue [Feature]: Pull a project into a new window #2267 covers pulling a project into a new window, which helps but doesn't solve the organizational problem within a single window.
• Manual naming conventions — prefixing project names with context (e.g. [Work] my-app) is fragile and doesn't scale.

Risks or tradeoffs

• Adds state management complexity (persisting Space assignments, active Space, ordering).
• Need to decide what happens to unassigned/new projects — a sensible default (e.g. a "Default" space or the active space) keeps onboarding simple.
• Should consider whether threads are Space-scoped or project-scoped (projects already imply a grouping for their threads, so Space-scoping projects likely suffices).

Examples or references

• Arc Browser Spaces — vertical Space switcher on the left edge, each Space has its own tabs, bookmarks, and pinned sites.
• Zen Browser Workspaces — similar concept with workspace switching.
• VS Code's multi-root workspaces and JetBrains' project groups solve a related problem in IDEs.

Contribution

• I would be open to helping implement this.