How do I open an already-loaded buffer in a new tab without re-reading it from disk?

Explanation

If a file is already loaded as a buffer, reopening it with :tabedit can trigger another read and may lose the exact in-memory context you want. :tab sbuffer opens that existing buffer in a new tab page directly, which is ideal when you want a focused workspace while keeping the original window setup intact. This is especially useful during refactors where one buffer is a reference and another is your active edit surface.

How it works

• :tab runs the following command in a new tab page
• sbuffer {bufnr} opens an existing buffer in a split-style context without creating a new buffer instance
• {bufnr} is the numeric buffer ID (check with :ls)

Because it reuses a loaded buffer, you keep unsaved in-memory state and avoid duplicate buffer confusion.

Example

List buffers first:

:ls

Assume buffer 7 is a reference file you want in a dedicated tab. Run:

:tab sbuffer 7

Now that same buffer opens in a new tab, while your original tab layout remains available.

Tips

• Use :ls t to include tab/window placement when choosing the target buffer
• Combine with :keepalt if you need to preserve alternate-file behavior in larger workflows
• Prefer this over reopening paths when you care about exact buffer state