diff --git a/lib/cfgpath/cfgpath.h b/lib/cfgpath/cfgpath.h
--- a/lib/cfgpath/cfgpath.h
+++ b/lib/cfgpath/cfgpath.h
@@ -43,7 +43,7 @@
 #include <sys/param.h>
 #endif
 
-#if defined(__linux__) || defined(BSD)
+#if defined(__linux__) || defined(BSD) || defined(__EMSCRIPTEN__)
 #define CFGPATH_LINUX
 #include <string.h>
 #include <stdlib.h>
diff --git a/src/lincity/MapPoint.hpp b/src/lincity/MapPoint.hpp
--- a/src/lincity/MapPoint.hpp
+++ b/src/lincity/MapPoint.hpp
@@ -27,9 +27,8 @@
 #include <cstddef>        // for size_t
 #include <ostream>        // for ostream
 
-namespace std {
-template<class Key> struct hash; // IWYU pragma: keep
-}  // namespace std
+#include <functional>     // for hash (fredygames: libc++ keeps std::hash in an
+                          // inline namespace, so it cannot be forward-declared)
 
 class MapPoint {
 public:
diff --git a/src/lincity-ng/Game.cpp b/src/lincity-ng/Game.cpp
--- a/src/lincity-ng/Game.cpp
+++ b/src/lincity-ng/Game.cpp
@@ -21,6 +21,9 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 ** ---------------------------------------------------------------------- */
 
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#endif
 #include "Game.hpp"
 
 #include <SDL3/SDL.h>                       // for SDL_KeyCode, Uint32, SDL_...
@@ -493,6 +496,10 @@
             SDL_Event event;
             int event_timeout = next_task - SDL_GetTicks();
             if(event_timeout < 0) event_timeout = 0;
+#ifdef __EMSCRIPTEN__
+            // fredygames: let the browser run even when a task is overdue
+            if(event_timeout == 0) emscripten_sleep(0);
+#endif
             int status = SDL_WaitEventTimeout(&event, event_timeout);
             if(!status) break; // timed out
 
diff --git a/src/lincity-ng/GameView.cpp b/src/lincity-ng/GameView.cpp
--- a/src/lincity-ng/GameView.cpp
+++ b/src/lincity-ng/GameView.cpp
@@ -124,7 +124,14 @@
   blankGraphicsInfo.y = blankGraphicsInfo.texture->getHeight();
 
   stopThread = false;
+#ifdef __EMSCRIPTEN__
+  // fredygames: no threads in the browser build
+  loaderThread = NULL;
+  preReadImages();
+  textures_ready = true;
+#else
   loaderThread = SDL_CreateThread( gameViewThread, "Loader", this );
+#endif
 
   //GameView is resizable
   setFlags(FLAG_RESIZABLE);
diff --git a/src/lincity-ng/main.cpp b/src/lincity-ng/main.cpp
--- a/src/lincity-ng/main.cpp
+++ b/src/lincity-ng/main.cpp
@@ -23,6 +23,10 @@
 
 #include "main.hpp"
 
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#endif
+
 #include <SDL3/SDL.h>                            // for SDL_GetError, SDL_Se...
 #include <SDL3_ttf/SDL_ttf.h>                    // for TTF_Init, TTF_Quit
 #include <fmt/base.h>                            // for println
@@ -237,6 +241,16 @@
   MainMenu(window).run();
 }
 
+#ifdef __EMSCRIPTEN__
+// fredygames: the page calls this when the tab is hidden or closed, so the
+// options reach the browser storage even if the game never quits.
+static bool fredygamesReady = false;
+extern "C" EMSCRIPTEN_KEEPALIVE void fredygames_save() {
+  if(fredygamesReady)
+    getConfig()->save();
+}
+#endif
+
 int
 main(int argc, char** argv) {
   // initialize XML parser early because it is needed for parsing the config
@@ -289,6 +303,9 @@
   initVideo(getConfig()->videoX.get(), getConfig()->videoY.get());
   initLincity();
   std::unique_ptr<Sound> sound(new Sound());
+#ifdef __EMSCRIPTEN__
+  fredygamesReady = true;
+#endif
 
   // enter main loop
   mainLoop();
diff --git a/src/lincity-ng/MainMenu.cpp b/src/lincity-ng/MainMenu.cpp
--- a/src/lincity-ng/MainMenu.cpp
+++ b/src/lincity-ng/MainMenu.cpp
@@ -21,6 +21,9 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 ** ---------------------------------------------------------------------- */
 
+#ifdef __EMSCRIPTEN__
+#include <emscripten.h>
+#endif
 #include "MainMenu.hpp"
 
 #include <SDL3/SDL.h>                   // for SDL_EventType, Uint32, SDL_Ge...
@@ -869,6 +872,10 @@
             SDL_Event event;
             int event_timeout = next_task - SDL_GetTicks();
             if(event_timeout < 0) event_timeout = 0;
+#ifdef __EMSCRIPTEN__
+            // fredygames: let the browser run even when a task is overdue
+            if(event_timeout == 0) emscripten_sleep(0);
+#endif
             int status = SDL_WaitEventTimeout(&event, event_timeout);
             if(!status) break; // timed out
 
diff --git a/src/lincity-ng/Sound.cpp b/src/lincity-ng/Sound.cpp
--- a/src/lincity-ng/Sound.cpp
+++ b/src/lincity-ng/Sound.cpp
@@ -259,7 +259,11 @@
         return;
     } else {
         audioOpen = true;
+#ifdef __EMSCRIPTEN__
+        soundThread(this); // fredygames: no threads in the browser build
+#else
         loaderThread = SDL_CreateThread(soundThread, "Sound", this);
+#endif
     }
 
     musicTrack = MIX_CreateTrack(mixer);