Fix GTK4 API issues and auto-preload gtk4-layer-shell

- Use property setter for PasswordEntry placeholder text
- Remove unsupported max-width/max-height from CSS
- Set avatar size via set_size_request()
- Auto re-exec with LD_PRELOAD for gtk4-layer-shell linking order

src/moonlock/lockscreen.py

@@ -71,8 +71,10 @@ class LockscreenWindow(Gtk.ApplicationWindow):
         if avatar_path:
             avatar = Gtk.Picture.new_for_filename(str(avatar_path))
             avatar.set_content_fit(Gtk.ContentFit.COVER)
+            avatar.set_size_request(128, 128)
         else:
             avatar = Gtk.Box()
+            avatar.set_size_request(128, 128)
         avatar.set_halign(Gtk.Align.CENTER)
         avatar.add_css_class("avatar")
         self._login_box.append(avatar)
@@ -84,8 +86,8 @@ class LockscreenWindow(Gtk.ApplicationWindow):
 
         # Password entry
         self._password_entry = Gtk.PasswordEntry()
-        self._password_entry.set_placeholder_text(self._strings.password_placeholder)
-        self._password_entry.set_show_peek_icon(True)
+        self._password_entry.set_property("placeholder-text", self._strings.password_placeholder)
+        self._password_entry.set_property("show-peek-icon", True)
         self._password_entry.add_css_class("password-entry")
         self._password_entry.connect("activate", self._on_password_submit)
         self._login_box.append(self._password_entry)

src/moonlock/main.py

@@ -1,9 +1,16 @@
 # ABOUTME: Entry point for Moonlock — sets up GTK Application and ext-session-lock-v1.
 # ABOUTME: Handles CLI invocation, session locking, and multi-monitor support.
 
+import os
 import sys
 from importlib.resources import files
 
+# gtk4-layer-shell must be loaded before libwayland-client
+_LAYER_SHELL_LIB = "/usr/lib/libgtk4-layer-shell.so"
+if "LD_PRELOAD" not in os.environ and os.path.exists(_LAYER_SHELL_LIB):
+    os.environ["LD_PRELOAD"] = _LAYER_SHELL_LIB
+    os.execvp(sys.executable, [sys.executable, "-m", "moonlock.main"] + sys.argv[1:])
+
 import gi
 gi.require_version("Gtk", "4.0")
 gi.require_version("Gdk", "4.0")

src/moonlock/style.css

@@ -20,8 +20,6 @@ window.lockscreen {
     border-radius: 50%;
     min-width: 128px;
     min-height: 128px;
-    max-width: 128px;
-    max-height: 128px;
     background-color: @theme_selected_bg_color;
     border: 3px solid alpha(white, 0.3);
 }