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src/fade_black.rs

@@ -1,3 +1,5 @@
+// Layer shell surface that fades to black, before setting DPMS off.
+
 use keyframe::{ease, functions::EaseInOut};
 use std::time::{Duration, Instant};
 use wayland_client::{

src/freedesktop_screensaver.rs

@@ -88,6 +88,7 @@ pub async fn serve(conn: &zbus::Connection, event_sender: EventSender) -> zbus::
         )
         .await?;
 
+    // If a client disconnects from DBus, remove any inhibitors it has added.
     let dbus = zbus::fdo::DBusProxy::new(conn).await?;
     let mut name_owner_stream = dbus.receive_name_owner_changed().await?;
     while let Some(event) = name_owner_stream.next().await {

src/main.rs

@@ -147,12 +147,14 @@ impl State {
         }
     }
 
+    // If screen off or suspend idle times have changed, recreate idle notifications.
     fn recreate_notification(&mut self) {
         if self.screen_off_idle_notification.as_ref().map(|x| x.time) != self.conf.screen_off_time {
             self.screen_off_idle_notification = self
                 .conf
                 .screen_off_time
                 .map(|time| IdleNotification::new(&self.inner, time));
+            // Initially not idle; server sends `resumed` only after `idled`
             self.update_screen_off_idle(false);
         }
         let suspend_time = if self.on_battery {
@@ -163,6 +165,7 @@ impl State {
         if self.suspend_idle_notification.as_ref().map(|x| x.time) != suspend_time {
             self.suspend_idle_notification =
                 suspend_time.map(|time| IdleNotification::new(&self.inner, time));
+            // Initially not idle; server sends `resumed` only after `idled`
             self.update_suspend_idle(false);
         }
     }