ext/pyrender/viewer: resolve macOS crashes when initialising Tk()

genesis/ext/pyrender/viewer.py

@@ -16,6 +16,8 @@
 
 from tkinter import Tk
 from tkinter import filedialog
+root = Tk()
+root.withdraw()
 
 import pyglet
 from moviepy.video.io.ffmpeg_writer import FFMPEG_VideoWriter
@@ -961,7 +963,6 @@ def _get_save_filename(self, file_exts):
         }
         filetypes = [file_types[x] for x in file_exts]
         try:
-            root = Tk()
             save_dir = self.viewer_flags["save_directory"]
             if save_dir is None:
                 save_dir = os.getcwd()