OSC 51 Reserved for Emacs
A number xterm sets aside for the Emacs shell, and does nothing with itself.
OSC 51 ; Pt ST
xterm’s Control Sequences document lists OSC 51 as “reserved for Emacs shell”: a number set aside so that Emacs’s terminal modes can use it for their own messages without clashing with anything xterm does. Emacs’s vterm package, for one, sends commands to Emacs through it. xterm itself does nothing with it (do_osc), and neither does libghostty-vt, which passes.
Validation
OSC51-1: Ignored
A
\e]51;Efind-file "~/notes"\a
B
|AB____|
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