diff --git a/source/core/rendering/sdl_manager.cpp b/source/core/rendering/sdl_manager.cpp
index 6d4d587..a4d2bde 100644
--- a/source/core/rendering/sdl_manager.cpp
+++ b/source/core/rendering/sdl_manager.cpp
@@ -254,6 +254,10 @@ void SDLManager::toggleFullscreen() {
         windowed_width_ = current_width_;
         windowed_height_ = current_height_;
         is_fullscreen_ = true;
+        // SDL3: cal seleccionar explícitament el mode "borderless desktop"
+        // (mode=nullptr) abans d'activar el fullscreen. Sense això, el
+        // comportament depèn del mode que tingués la finestra anteriorment.
+        SDL_SetWindowFullscreenMode(finestra_, nullptr);
         SDL_SetWindowFullscreen(finestra_, true);
         std::cout << "F3: Fullscreen activat (guardada: "
                   << windowed_width_ << "x" << windowed_height_ << ")" << '\n';