Enter key does nothing in panes when host terminal is Konsole (CSI-u Enter parsed as Unsupported)

[JHXs]

• I confirm this is a reproducible bug, not a feature request, idea, question, contribution proposal, or direction check.
• I reproduced this bug on the version and environment reported below using the exact steps provided.

Current behavior

Pressing Enter inside a herdr pane does nothing: commands typed at a shell prompt never execute, and the prompt stays on the current line. This affects every space/pane in the session, not one particular pane. All other keys (letters, space, backspace) work normally.

The same Enter key works fine in a plain Konsole shell without herdr, and herdr behaves correctly when the outer terminal is kitty.

With HERDR_LOG=herdr=debug, every Enter press from the Konsole host is logged as event=Unsupported and never reaches the pane, e.g.:

DEBUG herdr::raw_input: raw input event parsed raw_bytes=[27, 91, 49, 51, 59, 49, 59, 49, 51, 117] event=Unsupported
DEBUG herdr::raw_input: raw input event parsed raw_bytes=[27, 91, 49, 51, 59, 49, 58, 51, 59, 49, 51, 117] event=Unsupported

i.e. the Konsole host sends Enter as ESC[13;1;13u (press) and ESC[13;1:3;13u (release), which herdr marks Unsupported and drops.

Expected behavior

Enter should execute or complete the current line in the focused pane, as it does outside herdr and under other terminals.

Reproduction

1. Install herdr 0.9.0 and run it inside Konsole 26.08.0 (KDE Plasma; TERM=xterm-256color). No tmux involved.
2. Open any workspace/pane with a shell (e.g. fish or bash).
3. Type a command and press Enter. Nothing happens; other keys still work.
4. Optional: relaunch with HERDR_LOG=herdr=debug herdr to see the Enter sequence logged as Unsupported and dropped.

Impact

herdr is unusable from Konsole — every Enter-based submission in any pane is lost. I work around it by using kitty as the outer terminal, which works correctly.

Environment

• Herdr version: 0.9.0 (client and server, updated 2026-09-08)
• Update channel (stable or preview): stable
• Operating system: EndeavourOS (Arch), kernel 7.2.3-arch1-3, x86_64, local session
• Terminal: Konsole 26.08.0, TERM=xterm-256color
• Shell, if relevant: fish (issue occurs in any shell in a pane)
• Relevant config, if any: default config.toml (no custom keybindings)

[akbash-bot]

This is the same input-parser bug tracked in #3589. Both reports show Enter arriving as CSI 13;1;13u with its control value in the associated-text field, which Herdr rejects. #3589 already has the fix in #3592, so I’m consolidating this report there. If a concrete detail shows a different failure after that fix lands, please reply here and tag a maintainer.