Multi-row tabs: wrap tabs to additional rows when the tab bar overflows

[daniilsimakhin]

Body

Multi-row tabs: wrap tabs to additional rows when the tab bar overflows

Problem

Currently, when the number of open tabs exceeds the tab bar width, Zed switches to horizontal scrolling. This works for a small number of overflow tabs, but breaks down in common real-world scenarios:

• Refactoring across modules — when you have 15–25 files open across several layers of an app (controllers, services, models, tests), only the few leftmost or rightmost tabs are visible. You constantly lose the visual overview of what you have open.
• Debugging sessions — jumping between related files (a controller, a service it calls, the model, the migration, the test) means scrolling left and right repeatedly just to find a tab you opened two minutes ago.
• Wide monitors are wasted — on a 27" or ultrawide display, there is plenty of vertical space, but tabs are constrained to a single horizontal strip. The bar gets wider but tabs still overflow once you cross ~20 files.
• Tab names become unreadable — even before scrolling kicks in, tabs are shrunk so aggressively that filenames are truncated to 3–4 characters, making them indistinguishable (especially with files like index.php, User.php, Controller.php in nested folders).
  The result is that experienced users coming from JetBrains, Visual Studio, or VS Code (with editor.wrapTabs) feel a noticeable productivity regression in Zed for projects with many open files.

Current workarounds and their limits

I am aware of and use the following, but each has limits:

• max_tabs — auto-closes old tabs. Helps, but you lose context: a file you actually want to keep open gets closed without warning.
• Preview tabs — great for navigation, but doesn't help once you've started editing several files.
• tab_bar.show_pinned_tabs_in_separate_row (#46573) — excellent step in the right direction. Solves the pinned-vs-working tabs split, but doesn't help when the working row itself overflows.
• Cmd+E / Recent Files, Tab Switcher — useful for navigation, but it's a modal popup. It doesn't give you the constant peripheral awareness of "what's open right now" that a visible tab bar does.
• Splits — solve a different problem (parallel editing of two files), not "I have 20 files open and need to glance between them".

Proposed solution

Introduce an opt-in setting that wraps tabs onto additional rows when the tab bar overflows, instead of (or in addition to) horizontal scrolling.

Suggested setting shape (consistent with the existing show_pinned_tabs_in_separate_row):

{
  "tab_bar": {
    "wrap": "off" | "on" | "auto",
    "max_rows": 3
  }
}

• wrap: "off" (default) — preserves current single-row behavior. Zero impact on existing users.
• wrap: "on" — tabs always wrap to additional rows as needed.
• wrap: "auto" — wraps only when the number of tabs exceeds a threshold (or when horizontal scrolling would otherwise kick in).
• max_rows — optional cap. Beyond this number of rows, fall back to horizontal scrolling on the last row. Prevents the tab bar from consuming half the screen on extreme cases.

Design notes

A few details worth deciding up-front:

• Stable ordering on close/open. When a tab closes, remaining tabs should ideally not reflow across rows, to preserve muscle memory of "where is that file in the bar". Microsoft has a good discussion of this trade-off in vscode#80510 ("shelves" concept).
• Interaction with pinned-row split. Should compose cleanly with show_pinned_tabs_in_separate_row: pinned tabs in row 1, working tabs wrapping across rows 2..N.
• Drag and drop across rows. Needs to work, but is a natural extension of existing D&D within a row.
• Keyboard navigation. Ctrl+Tab, Cmd+Alt+→/←, and similar should treat the wrapped rows as one logical sequence (end of row 1 → start of row 2).
• Scrollbar buttons. When max_rows is hit and horizontal scrolling kicks in on the last row, existing scroll buttons should keep working.

Prior art

This is a well-established pattern in IDEs that target the same audience as Zed:

• JetBrains IDEs (IntelliJ IDEA, WebStorm, PyCharm, RubyMine, PhpStorm) — Settings → Editor → General → Editor Tabs → Show tabs in multiple rows.
• Visual Studio — multi-row tabs built in by default.
• Eclipse — multi-row tabs.
• VS Code — workbench.editor.wrapTabs (microsoft/vscode#32836, shipped 2021).
  The fact that all four major desktop IDEs converged on this feature suggests it's solving a real problem that single-row + horizontal scroll doesn't.

Why this fits Zed

• Opt-in by default — existing users see zero change. The minimalist default UI is preserved.
• Composes with existing work — builds on the architecture already introduced by #46573 (separate render method for the new layout, shared sub-components).
• Addresses a frequent migration pain point — many Zed adopters come from JetBrains products, and this is consistently one of the first things they miss.
• Doesn't replace any existing flow — splits, Cmd+E, tab switcher, preview tabs all remain useful for their own use cases.