From 06086de3288df6545204225665192e99634741b2 Mon Sep 17 00:00:00 2001
From: enricobuehler <buehler@unom.io>
Date: Sun, 9 Aug 2026 00:24:15 +0200
Subject: [PATCH] =?UTF-8?q?fix(windows/cursor):=20do=20the=20clean=20on=20?=
 =?UTF-8?q?the=20ADD=20path=20=E2=80=94=20the=20handshake=20call=20site=20?=
 =?UTF-8?q?was=20never=20reached?=
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Third and last placement bug in this chain. clean_cursor_for_next_session was
called from the handshake, inside the '#[cfg(windows)] let prep = match (source,
compositor) { (Virtual, Some(comp)) => ...' arm — which is not the path taken on
this host, so the function never ran. The logs said so by omission: no 'skipping'
line, no 'recycled' line, and cursor_excluded stayed true across the reconnect.

Move it next to where the declare is recorded: the ADD request. Every session
that creates a monitor goes through it, with hw_cursor in hand, before the
monitor exists — which is also the moment the recycle is safe.
---
 crates/pf-vdisplay/src/vdisplay/windows/pf_vdisplay.rs | 8 ++++++++
 crates/punktfunk-host/src/native/handshake.rs          | 7 -------
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/crates/pf-vdisplay/src/vdisplay/windows/pf_vdisplay.rs b/crates/pf-vdisplay/src/vdisplay/windows/pf_vdisplay.rs
index d765be73..fb27471c 100644
--- a/crates/pf-vdisplay/src/vdisplay/windows/pf_vdisplay.rs
+++ b/crates/pf-vdisplay/src/vdisplay/windows/pf_vdisplay.rs
@@ -894,6 +894,14 @@ impl VdisplayDriver for PfVdisplayDriver {
         client_hdr: Option<punktfunk_core::quic::HdrMeta>,
         hw_cursor: bool,
     ) -> Result<AddedMonitor> {
+        // Give a capture-mode session the LOSSLESS pointer back: if an earlier session declared a
+        // hardware cursor and this one does not want it, recycle the driver's host process BEFORE
+        // this monitor is added. The ADD path is the only place guaranteed to see every session
+        // (the handshake call site this replaced sat in a `match (source, compositor)` arm that is
+        // not taken on this host, so it never ran).
+        if !hw_cursor {
+            clean_cursor_for_next_session(false);
+        }
         let session_id = next_session_id();
         // The client display's volume rides into the monitor's EDID CTA HDR block; all-zero =
         // unknown → the driver keeps its built-in defaults (also what an un-upgraded driver, which
diff --git a/crates/punktfunk-host/src/native/handshake.rs b/crates/punktfunk-host/src/native/handshake.rs
index 601eee6d..18a76d5d 100644
--- a/crates/punktfunk-host/src/native/handshake.rs
+++ b/crates/punktfunk-host/src/native/handshake.rs
@@ -686,13 +686,6 @@ pub(super) async fn negotiate(
             // The bit the Welcome just advertised — read back rather than recomputed, so the
             // prepared display and the session wiring cannot disagree with it.
             let cursor_fw = welcome.host_caps & punktfunk_core::quic::HOST_CAP_CURSOR != 0;
-            // Give a capture-mode session back the LOSSLESS pointer: if an earlier session on this
-            // host declared the hardware cursor (desktop mouse model) and this one did not ask for
-            // it, clear the sticky declare now — BEFORE this session's display is created, which is
-            // the only safe moment, and exactly the "desktop session, disconnect, reconnect in
-            // capture mode" case the start-up clean cannot reach. No-op when nothing declared, when
-            // this session wants the channel, or when any display is still held.
-            pf_vdisplay::driver::clean_cursor_for_next_session(cursor_fw);
             // Same bit the data plane's SessionContext reads — the prepared plan and the
             // session wiring must agree on the slicing ceiling (an encoder rebuilt from the
             // prepared plan with a DIFFERENT max_slices would change the wire shape mid-flow).