diff -ruN a/game.cpp b/game.cpp
--- a/game.cpp
+++ b/game.cpp
@@ -5674,3 +5674,14 @@
 	return JNI_VERSION_1_6;
 }
 #endif
+
+
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+/* Called by the page when the tab is hidden or closed: saves the game in progress. */
+extern "C" EMSCRIPTEN_KEEPALIVE void fredygames_save() {
+	if( game_g != NULL ) {
+		game_g->saveState();
+	}
+}
+#endif
diff -ruN a/screen.cpp b/screen.cpp
--- a/screen.cpp
+++ b/screen.cpp
@@ -3,6 +3,9 @@
 
 #include <cassert>
 #include <ctime>
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#endif
 
 #include "screen.h"
 #include "sound.h"
@@ -377,6 +380,10 @@
 		 * TICK_INTERVAL.
 		 */
 		wait();
+#ifdef __EMSCRIPTEN__
+		// hand the turn back to the browser, which paints and delivers input in between
+		emscripten_sleep(0);
+#endif
 
 		unsigned int new_time = game_g->getApplication()->getTicks();
 		//LOG("%d, %d\n", new_time, new_time - elapsed_time);