fix: prevent sticky sidebar hover drag state

static/sessions.js

@@ -2509,15 +2509,31 @@ function renderSessionListFromCache(){
     let _tapTimer=null;
     let _pointerDownX=0;
     let _pointerDownY=0;
+    let _pointerActive=false;
     let _isDragging=false;
     let _clearDragTimer=null;
+    const _clearPointerDragState=()=>{
+      _pointerActive=false;
+      if(_isDragging){
+        _isDragging=false;
+        if(_clearDragTimer){clearTimeout(_clearDragTimer);_clearDragTimer=null;}
+        _clearDragTimer=setTimeout(()=>{el.classList.remove('dragging');_clearDragTimer=null;},50);
+      }
+    };
     el.onpointerdown=(e)=>{
       if(e.pointerType==='mouse' && e.button!==0) return;
+      _pointerActive=true;
       _pointerDownX=e.clientX;
       _pointerDownY=e.clientY;
       _isDragging=false;
+      if(_clearDragTimer){clearTimeout(_clearDragTimer);_clearDragTimer=null;}
+      el.classList.remove('dragging');
     };
     el.onpointermove=(e)=>{
+      // Plain hover also dispatches pointermove. Only mark a row as dragging
+      // after an actual press starts on this row; otherwise hovered rows stay
+      // faded until the next sidebar rerender clears their DOM nodes.
+      if(!_pointerActive) return;
       if(_isDragging) return;
       const dx=Math.abs(e.clientX-_pointerDownX);
       const dy=Math.abs(e.clientY-_pointerDownY);
@@ -2528,8 +2544,11 @@ function renderSessionListFromCache(){
         if(_clearDragTimer){clearTimeout(_clearDragTimer);_clearDragTimer=null;}
       }
     };
+    el.onpointercancel=_clearPointerDragState;
+    el.onpointerleave=()=>{ if(_pointerActive) _clearPointerDragState(); };
     el.onpointerup=(e)=>{
       if(e.pointerType==='mouse' && e.button!==0) return;  // ignore right/middle click
+      _pointerActive=false;
       if(_renamingSid) return;
       if(actions&&actions.contains(e.target)) return;
       if(e.target&&e.target.closest&&e.target.closest('.session-child-count,.session-child-sessions,.session-child-session')) return;

tests/test_issue500_session_list_virtualization.py

@@ -2,6 +2,7 @@
 import json
 import shutil
 import subprocess
+import tempfile
 from pathlib import Path
 
 import pytest
@@ -14,13 +15,21 @@ pytestmark = pytest.mark.skipif(NODE is None, reason="node not on PATH")
 
 
 def _run_node(source: str) -> str:
-    result = subprocess.run(
-        [NODE, "-e", source],
-        cwd=str(REPO_ROOT),
-        capture_output=True,
-        text=True,
-        timeout=10,
-    )
+    with tempfile.NamedTemporaryFile(
+        "w", suffix=".cjs", encoding="utf-8", dir=REPO_ROOT, delete=False
+    ) as script:
+        script.write(source)
+        script_path = Path(script.name)
+    try:
+        result = subprocess.run(
+            [NODE, str(script_path)],
+            cwd=str(REPO_ROOT),
+            capture_output=True,
+            text=True,
+            timeout=10,
+        )
+    finally:
+        script_path.unlink(missing_ok=True)
     if result.returncode != 0:
         raise RuntimeError(result.stderr)
     return result.stdout.strip()

tests/test_issue856_pinned_indicator_layout.py

@@ -116,6 +116,15 @@ def test_timestamp_hidden_when_attention_state_is_present():
     assert ".session-item.unread:not(:hover):not(:focus-within):not(.menu-open) .session-actions" in STYLE_CSS
 
 
+def test_plain_mouse_hover_does_not_mark_session_row_dragging():
+    """Pointermove fires during ordinary hover; drag styling must require an active press."""
+    assert "let _pointerActive=false;" in SESSIONS_JS
+    assert "_pointerActive=true;" in SESSIONS_JS
+    assert "if(!_pointerActive) return;" in SESSIONS_JS
+    assert "_pointerActive=false;" in SESSIONS_JS
+    assert ".session-item.dragging:hover" in STYLE_CSS
+
+
 def test_sidebar_uses_local_inflight_state_for_immediate_spinner():
     messages_js = (Path(__file__).resolve().parent.parent / "static" / "messages.js").read_text()