diff --git a/BasiliskII/TODO b/BasiliskII/TODO
index 4f5bc5eb..4e5f1eb8 100644
--- a/BasiliskII/TODO
+++ b/BasiliskII/TODO
@@ -50,4 +50,3 @@ Windows
 - video_windows.cpp: implement with DirectX
 - audio_windows.cpp, scsi_windows.cpp: merge from original Windows version
 - GUI: handle NDIS interfaces
-- GUI: make switch to "Fullscreen" mode set "frameskip" to 0
diff --git a/BasiliskII/src/Windows/prefs_editor_gtk.cpp b/BasiliskII/src/Windows/prefs_editor_gtk.cpp
index 938c08b5..8e8eeca5 100644
--- a/BasiliskII/src/Windows/prefs_editor_gtk.cpp
+++ b/BasiliskII/src/Windows/prefs_editor_gtk.cpp
@@ -833,6 +833,7 @@ static void mn_fullscreen(...)
 {
 	display_type = DISPLAY_SCREEN;
 	hide_show_graphics_widgets();
+	PrefsReplaceInt32("frameskip", 1);
 }
 
 // "5 Hz".."60Hz" selected