Windows support

Widgets.py

@@ -12,7 +12,7 @@ from typing import Callable, Optional
 
 import flet as ft
 
-from Core import AppConfig, ChildEnvironment, ChipButton, Note, NotificationStyle, Palette
+from Core import AppConfig, ChildEnvironment, ChipButton, IsWindows, Note, NotificationStyle, Palette
 from Library import ConfValue
 
 
@@ -72,7 +72,7 @@ class App:
         else to the default app."""
         from Query import VideoExtensions
 
-        Command = ["xdg-open", str(TargetPath)]
+        Command = None if IsWindows else ["xdg-open", str(TargetPath)]  # Windows: os.startfile below
         if TargetPath.suffix.lower() in VideoExtensions:
             Player = str(ConfValue("Media", "VideoPlayer", "") or "").strip()
             if Player and shutil.which(Player.split()[0]):
@@ -80,8 +80,11 @@ class App:
             elif Player:
                 self.Notify(f"Video player '{Player}' isn't installed; using the default app.", "warning")
         try:
-            subprocess.Popen(Command, env=ChildEnvironment(), start_new_session=True,
-                             stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+            if Command is None:
+                os.startfile(str(TargetPath))  # the default app
+            else:
+                subprocess.Popen(Command, env=ChildEnvironment(), start_new_session=True,
+                                 stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
         except OSError as Error:
             self.Notify(f"Couldn't open {TargetPath.name}: {Error}", "error")