fix(modal): drop the PANELS borrow before closing drawer windows (#627)

trollshell/src/modal.rs

@@ -950,6 +950,15 @@ fn wire_retract_finish(revealer: &gtk::Revealer, key: String) {
         }
         let closed_plugin_panel = PANELS.with(|panels| {
             let panels = panels.borrow();
+            // Post-#627, `close_all` drains every entry out of `PANELS` before
+            // closing any window, so a synchronous `child-revealed` emission
+            // during one of those closes now always lands here (this key is
+            // already gone). Benign: `close_all`'s own tail performs
+            // everything the `Some` arm below would have —
+            // `set_visible(false)` on a window that's being dropped anyway,
+            // `*current = None`, `open_state.set(false)`, and
+            // (unconditionally) `set_active_panel(None)` — so returning
+            // `false` here just skips redundant work, not a missed teardown.
             let Some(panel) = panels.get(&key) else {
                 return false;
             };
@@ -973,12 +982,24 @@ fn wire_retract_finish(revealer: &gtk::Revealer, key: String) {
 }
 
 /// Close and remove all drawers (called before rebuilding bars on hot-plug).
+///
+/// Drains `PANELS` into a local `Vec` and drops the borrow *before* calling
+/// `gtk::Window::close` on each entry, rather than closing from inside the
+/// `borrow_mut()` (#627). `wire_retract_finish`'s `child-revealed` handler
+/// takes its own `borrow()` of the same `RefCell`; if `close()` ever
+/// triggered that signal synchronously, running it under an active
+/// `borrow_mut()` would panic, and a panic unwinding through a glib callback
+/// aborts the process. Whether `gtk_window_close`/`gtk_revealer_unmap` can
+/// emit `notify::child-revealed` synchronously is not verified either way —
+/// draining first removes the dependency on that question entirely, which is
+/// the point: not holding the borrow is free, so there's no need to resolve
+/// it first.
 pub fn close_all() {
-    PANELS.with(|panels| {
-        for (_, panel) in panels.borrow_mut().drain() {
-            panel.window.close();
-        }
-    });
+    let panels: Vec<_> =
+        PANELS.with(|panels| panels.borrow_mut().drain().map(|(_, v)| v).collect());
+    for panel in panels {
+        panel.window.close();
+    }
     reset_drawer_open_states();
     // A monitor teardown that held the open plugin panel must clear the
     // selection too, so the v1 "hot-unplug just closes the plugin page with the