cua-driver-rs (Linux/Wayland): KDE Plasma 6.7 — agent cursor renders but input doesn't dispatch (portal-libei feature gated off in published binary)

User report

I tried using it on KDE Plasma 6.7 (Wayland) on Arch Linux, it didn't work, I saw the blue cursor but it didn't do the task I asked it to do, which was just to pause the music that was playing, and I specified the app.

Environment

• OS: Arch Linux
• DE: KDE Plasma 6.7 (Wayland)
• cua-driver: Linux published tarball (assumed current ≥ v0.6.0, please confirm)

Symptom

• Agent cursor (the colored overlay added in the Wayland-parity slice) renders correctly → confirms the overlay path via wp-fractional-scale-v1 + wp-viewporter is reaching the compositor.
• The requested action (pause music in a named app) does not execute → input dispatch is silently no-op'ing.
• App was named explicitly, so window resolution should have succeeded via ext-foreign-toplevel-list-v1.

Likely root cause

The native-Wayland parity work in #1966 added two input paths:

1. wlroots: zwlr_virtual_pointer_v1 — works on sway, Hyprland, labwc, wayfire, dwl. Not implemented by KWin/Plasma.
2. xdg-desktop-portal + libei: org.freedesktop.portal.RemoteDesktop.ConnectToEIS → reis (pure-Rust libei) — the only path that works on KDE Plasma / GNOME.

The libei path is feature-gated behind portal-libei in crates/platform-linux/Cargo.toml. It was gated off in the published binary by #1967 because the cross-platform CD's debian:11 build container ships PipeWire 0.3.19 (too old for libspa-sys 0.8 which needs ≥0.3.40) and has no libei-dev (added in trixie only). The Nix build enables --features portal-libei and works; the curl-pipe-bash tarball does not.

So on KDE Plasma:

• cursor overlay renders ✓ (no input needed)
• screencopy capture probably succeeds via wlroots screencopy if KWin exposes it, OR falls back to xdg-desktop-portal Screenshot
• input dispatch silently no-ops because wlr_virtual_pointer isn't advertised and portal_screencast/libei modules are #[cfg(feature = "portal-libei")]-gated out of the binary

Reproduction

Confirmed reproducible by anyone on KDE Plasma 6.x Wayland with a current Linux cua-driver tarball:

1. cua-driver list-windows → returns windows (works via ext-foreign-toplevel-list-v1).
2. cua-driver click ... against any of those windows → cursor moves visually, no actual click delivered.
3. cua-driver doctor → should currently report all-green even though input is dead.

Diagnostic to confirm

Once the user has tracing on, the log should show no attempt to use wlr_virtual_pointer (protocol not advertised) AND no attempt to use libei (compiled out). The bind loop in wayland::mod.rs will pick zero input-capable globals.

Options

1. Ship the published binary with portal-libei enabled. Requires either:

   • bumping the CD container to bookworm (PipeWire 0.3.65 has what libspa-sys needs) — but that raises the GLIBC floor 2.31 → 2.36 and breaks Ubuntu 22.04 / RHEL 9 / Debian 11 for the entire binary, not just Wayland features. Not acceptable — see #1925 + #1919.
   • vendoring newer PipeWire/libspa headers into the CD container — fragile.
   • Building two Linux variants per release: cua-driver-rs-<v>-linux-x86_64-binary.tar.gz (current, no portal-libei) and cua-driver-rs-<v>-linux-x86_64-portal.tar.gz (newer-glibc, full features). install.sh sniffs glibc and picks. Cleanest path forward.

2. doctor / runtime warning when the user is on KDE/GNOME and the portal-libei feature is gated off. At least surfaces "your DE needs the portal stack which isn't in this build" instead of silently no-op'ing input.

3. xdg-desktop-portal Screenshot + uinput fallback for input on systems without portal RemoteDesktop. Coarse but works without libei. Probably wrong long-term but cheap.

Recommendation

Land #2 first (one-day fix, ends the silent failure mode) → file #1 as the proper feature work. The two-variant publish is the canonical answer, mirrors how the wlroots-vs-portal split actually exists in the codebase.

References

• Wayland-parity PR that introduced the input paths: #1966
• Feature-gate that disabled portal-libei in the published binary: #1967
• GLIBC floor history: #1925 / #1919