How do I open another buffer in a split without changing the alternate-file register?

Explanation

The alternate-file register (#) is easy to disturb when jumping around buffers, and many advanced motions depend on it (<C-^>, # expansions, quick two-file toggles). :keepalt sbuffer {bufnr} opens a target buffer in a split while preserving your current alternate-file state. This is useful in review/debug sessions where you need temporary side windows but do not want to lose your primary file toggle context.

How it works

• :sbuffer {bufnr} opens an existing buffer in a new split
• :keepalt wraps the command so Vim does not update the alternate file
• {bufnr} can be any listed buffer number from :ls

Example

Imagine you are switching between app.py and test_app.py using <C-^>, and briefly need to inspect README.md.

:ls
:keepalt sbuffer 7

README.md opens in a split, but <C-^> still jumps between your original two files instead of being redirected to the temporary split target.

Tips

• Combine with :vert sbuffer {bufnr} when you prefer side-by-side layout
• Use this in custom commands/mappings where preserving # is important for muscle memory