OSC 9 ; 12 Prompt Start

OSC 9 ; 12 ST tells the terminal that the prompt starts at the cursor, so that it can find the prompts in what scrolled by. A shell sends it from its prompt string. It does the job of the A mark of OSC 133.

It is one of the commands ConEmu, a Windows terminal, put under OSC 9; the progress report page lists them all, and their definition is the ConEmu specific OSC table in ConEmu’s documentation. iTerm2 uses OSC 9 ; text ST for a notification, and a terminal that has both tells them apart by what follows the 9.

A default xterm ignores all of OSC 9, which is not among the OSC numbers it knows.

libghostty-vt marks the prompt, as it does for OSC 133, so the case is a known difference.

Validation

CONEMU12-1: The start of a prompt

\e]9;12\a
$

|$_____|
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