ESC [ 3 K: Erase Line Right Unless Pending Wrap
Found at https://terminalguide.netlify.com/seq/, urxvt supports this sequence.
As far as I recall, this is exactly what we do on ESC [ K
(740789).
We could make ESC [ 3 K
an alias for this (to encourage apps emitting this one, and eventually perhaps revert ESC [ K
to the official braindamaged behavior).
Edited by Egmont Koblinger