diff --git a/src/framework/Common.cpp b/src/framework/Common.cpp
index 6a91b3f..98739d4 100644
--- a/src/framework/Common.cpp
+++ b/src/framework/Common.cpp
@@ -5798,6 +5798,15 @@ void idCommonLocal::InitGame( void ) {
 		cvarSystem->SetCVarBool( "s_noSound", true );
 	} else {
 		// init OpenGL, which will open a window and connect sound and input hardware
+#ifdef __EMSCRIPTEN__
+		// InitGame runs before the first Emscripten frame, so normalize the
+		// browser-only video settings before renderer startup can select an
+		// optional desktop resolution-scale shader.
+		cvarSystem->SetCVarBool( "r_fullscreen", false );
+		cvarSystem->SetCVarInteger( "r_screenFraction", 100 );
+		cvarSystem->SetCVarInteger( "r_resolutionScaleMode", 0 );
+		cvarSystem->SetCVarInteger( "r_swapInterval", 1 );
+#endif
 		PrintLoadingMessage( common->GetLanguageDict()->GetString( "#str_104348" ) );
 		InitRenderSystem();
 	}
