Commit 4c34eeb416 fixed dead Ctrl+C by removing the Kitty protocol push
(CSI >1u) from _EXTENDED_ENTER_KEYS_SEQ, keeping only modifyOtherKeys
level 2. That regressed kitty-the-terminal completely: kitty removed
xterm modifyOtherKeys support (kovidgoyal/kitty#4075) and only speaks
its own protocol, so after the removal kitty users lost Shift+Enter and
every other extended key — the CSI >4;2m we still pushed is a no-op
there (kitty even logs a PARSE ERROR for it).
The original reason for removing the push is obsolete: #87511 mapped
CSI-u control sequences, so Ctrl+C as ESC[99;5u now parses to
Keys.ControlC and fires the existing c-c binding. (The kernel-INTR
concern in that commit was moot — prompt_toolkit's raw mode clears
ISIG, so Ctrl+C is always handled by the binding, never the kernel.)
Restore the dual push (CSI >1u + CSI >4;2m), exactly mirroring the Ink
TUI, and complete the alias table for what the kitty disambiguate flag
actually emits — #87511 left real gaps, some of which its PR body
wrongly claimed were covered:
- Esc key: ESC[27u (+ modifiers) — previously leaked '[27u' as text
- Ctrl+Backspace -> backward-kill-word (#78285 was closed on the wrong
claim that codepoint-127 mapping existed; it did not)
- Shift+Space -> space (#86866's second symptom; the Ctrl+Space
mapping never covered modifier 2)
- Alt+Enter -> newline tuple; Shift+Tab -> BackTab; Ctrl+Tab -> Tab;
Alt/Shift+Backspace
- Multi-modifier letters (Shift+Alt 4, Ctrl+Shift 6, Ctrl+Alt 7,
Ctrl+Alt+Shift 8) normalized onto their Ctrl/Escape-prefix targets,
both unshifted (kitty) and shifted (mok emitters) codepoints
- Kitty PUA functional keys: keypad -> non-keypad equivalents,
F13-F24, and Ignore for lock/media/modifier-event keys so they are
consumed instead of leaking (kitty emits these even in legacy mode)
Also: clear the VT100 parser's prefix cache after installing (stale
answers could misparse), and re-push extended keys after
_recover_terminal_input_modes' reset — the recovery previously popped
both modes mid-session and never re-enabled them, silently killing
Shift+Enter until restart.
Refs #87511, #87074, #56684, #56645, #78285, #86866, #87390.
kshitij
03bf85d83b