diff --git a/build/premake/extern_libs5.lua b/build/premake/extern_libs5.lua
index 17a15cec0e..eba9b52673 100644
--- a/build/premake/extern_libs5.lua
+++ b/build/premake/extern_libs5.lua
@@ -533,9 +533,9 @@ extern_lib_defs = {
 	},
 	spidermonkey = {
 		compile_settings = function()
-			if _OPTIONS["with-system-mozjs45"] then
+			if _OPTIONS["with-system-mozjs52"] then
 				if not _OPTIONS["android"] then
-					pkgconfig.add_includes("mozjs-45")
+					pkgconfig.add_includes("mozjs-52")
 				end
 			else
 				if os.istarget("windows") then
@@ -553,21 +553,21 @@ extern_lib_defs = {
 			end
 		end,
 		link_settings = function()
-			if _OPTIONS["with-system-mozjs45"] then
+			if _OPTIONS["with-system-mozjs52"] then
 				if _OPTIONS["android"] then
-					links { "mozjs-45" }
+					links { "mozjs-52" }
 				else
-					pkgconfig.add_links("mozjs-45")
+					pkgconfig.add_links("mozjs-52")
 				end
 			else
 				filter { "Debug", "action:vs2015" }
-					links { "mozjs45-ps-debug-vc140" }
+					links { "mozjs52-ps-debug-vc140" }
 				filter { "Release", "action:vs2015" }
-					links { "mozjs45-ps-release-vc140" }
+					links { "mozjs52-ps-release-vc140" }
 				filter { "Debug", "action:not vs*" }
-					links { "mozjs45-ps-debug" }
+					links { "mozjs52-ps-debug" }
 				filter { "Release", "action:not vs*" }
-					links { "mozjs45-ps-release" }
+					links { "mozjs52-ps-release" }
 				filter { }
 				add_source_lib_paths("spidermonkey")
 			end
diff --git a/build/premake/premake5.lua b/build/premake/premake5.lua
index c915b59b5b..5c8fe5e05e 100644
--- a/build/premake/premake5.lua
+++ b/build/premake/premake5.lua
@@ -6,7 +6,7 @@ newoption { trigger = "icc", description = "Use Intel C++ Compiler (Linux only;
 newoption { trigger = "jenkins-tests", description = "Configure CxxTest to use the XmlPrinter runner which produces Jenkins-compatible output" }
 newoption { trigger = "minimal-flags", description = "Only set compiler/linker flags that are really needed. Has no effect on Windows builds" }
 newoption { trigger = "outpath", description = "Location for generated project files" }
-newoption { trigger = "with-system-mozjs45", description = "Search standard paths for libmozjs45, instead of using bundled copy" }
+newoption { trigger = "with-system-mozjs52", description = "Search standard paths for libmozjs52, instead of using bundled copy" }
 newoption { trigger = "with-system-nvtt", description = "Search standard paths for nvidia-texture-tools library, instead of using bundled copy" }
 newoption { trigger = "without-audio", description = "Disable use of OpenAL/Ogg/Vorbis APIs" }
 newoption { trigger = "without-lobby", description = "Disable the use of gloox and the multiplayer lobby" }
diff --git a/libraries/osx/build-osx-libs.sh b/libraries/osx/build-osx-libs.sh
index c24fffe3fb..3a3a064102 100755
--- a/libraries/osx/build-osx-libs.sh
+++ b/libraries/osx/build-osx-libs.sh
@@ -48,12 +48,11 @@ MINIUPNPC_VERSION="miniupnpc-2.0.20180222"
 SODIUM_VERSION="libsodium-1.0.18"
 # --------------------------------------------------------------
 # Bundled with the game:
-# * SpiderMonkey 45
+# * SpiderMonkey
 # * NVTT
 # * FCollada
 # --------------------------------------------------------------
 # We use suffixes here in order to force rebuilding when patching these libs
-SPIDERMONKEY_VERSION="mozjs-45.0.2+wildfiregames.2"
 NVTT_VERSION="nvtt-2.1.1+wildfiregames.1"
 FCOLLADA_VERSION="fcollada-3.05+wildfiregames.1"
 # --------------------------------------------------------------
@@ -911,88 +910,16 @@ popd > /dev/null
 # be customized, so we build and install them from bundled sources
 # --------------------------------------------------------------------
 # SpiderMonkey - bundled, no download
-echo -e "Building SpiderMonkey..."
-
-LIB_VERSION="${SPIDERMONKEY_VERSION}"
-LIB_DIRECTORY="mozjs-45.0.2"
-LIB_ARCHIVE="$LIB_DIRECTORY.tar.bz2"
-
 pushd ../source/spidermonkey/ > /dev/null
 
-if [[ "$force_rebuild" = "true" ]] || [[ ! -e .already-built ]] || [[ "$(<.already-built)" != "$LIB_VERSION" ]]
+if [[ "$force_rebuild" = "true" ]]
 then
-  INSTALL_DIR="$(pwd)"
-  INCLUDE_DIR_DEBUG=$INSTALL_DIR/include-unix-debug
-  INCLUDE_DIR_RELEASE=$INSTALL_DIR/include-unix-release
-
   rm -f .already-built
-  rm -f lib/*.a
-  rm -rf $LIB_DIRECTORY $INCLUDE_DIR_DEBUG $INCLUDE_DIR_RELEASE
-  tar -xf $LIB_ARCHIVE
-
-  # Apply patches
-  pushd $LIB_DIRECTORY
-  . ../patch.sh
-  popd
-
-  pushd $LIB_DIRECTORY/js/src
-
-  CONF_OPTS="--target=$ARCH-apple-darwin
-    --prefix=${INSTALL_DIR}
-    --enable-posix-nspr-emulation
-    --with-system-zlib=${ZLIB_DIR}
-    --disable-tests
-    --disable-shared-js
-    --disable-jemalloc
-    --without-intl-api"
-  # Change the default location where the tracelogger should store its output, which is /tmp/ on OSX.
-  TLCXXFLAGS='-DTRACE_LOG_DIR="\"../../source/tools/tracelogger/\""'
-  if [[ $MIN_OSX_VERSION && ${MIN_OSX_VERSION-_} ]]; then
-    CONF_OPTS="$CONF_OPTS --enable-macos-target=$MIN_OSX_VERSION"
-  fi
-  if [[ $SYSROOT && ${SYSROOT-_} ]]; then
-    CONF_OPTS="$CONF_OPTS --with-macosx-sdk=$SYSROOT"
-  fi
-
-  # We want separate debug/release versions of the library, so change their install name in the Makefile
-  perl -i.bak -pe 's/(^STATIC_LIBRARY_NAME\s+=).*/$1'\''mozjs45-ps-debug'\''/' moz.build
-  mkdir -p build-debug
-  pushd build-debug
-  (CC="clang" CXX="clang++" CXXFLAGS="${TLCXXFLAGS}" AR=ar CROSS_COMPILE=1 \
-    ../configure $CONF_OPTS \
-        --enable-debug \
-        --disable-optimize \
-        --enable-js-diagnostics \
-        --enable-gczeal \
-    && make ${JOBS}) || die "SpiderMonkey build failed"
-  # js-config.h is different for debug and release builds, so we need different include directories for both
-  mkdir -p $INCLUDE_DIR_DEBUG
-  cp -R -L dist/include/* $INCLUDE_DIR_DEBUG/
-  cp dist/sdk/lib/*.a $INSTALL_DIR/lib
-  cp js/src/*.a $INSTALL_DIR/lib
-  popd
-  mv moz.build.bak moz.build
-
-  perl -i.bak -pe 's/(^STATIC_LIBRARY_NAME\s+=).*/$1'\''mozjs45-ps-release'\''/' moz.build
-  mkdir -p build-release
-  pushd build-release
-  (CC="clang" CXX="clang++" CXXFLAGS="${TLCXXFLAGS}" AR=ar CROSS_COMPILE=1 \
-    ../configure $CONF_OPTS \
-        --enable-optimize \
-    && make ${JOBS}) || die "SpiderMonkey build failed"
-  # js-config.h is different for debug and release builds, so we need different include directories for both
-  mkdir -p $INCLUDE_DIR_RELEASE
-  cp -R -L dist/include/* $INCLUDE_DIR_RELEASE/
-  cp dist/sdk/lib/*.a $INSTALL_DIR/lib
-  cp js/src/*.a $INSTALL_DIR/lib
-  popd
-  mv moz.build.bak moz.build
-  
-  popd
-  echo "$LIB_VERSION" > .already-built
-else
-  already_built
 fi
+
+# Use the regular build script for SM.
+JOBS="$JOBS" ZLIB_DIR="$ZLIB_DIR" ./build.sh
+
 popd > /dev/null
 
 # --------------------------------------------------------------
diff --git a/source/scriptinterface/ScriptTypes.h b/source/scriptinterface/ScriptTypes.h
index 7a7ff7075e..4aa195e352 100644
--- a/source/scriptinterface/ScriptTypes.h
+++ b/source/scriptinterface/ScriptTypes.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2016 Wildfire Games.
+/* Copyright (C) 2020 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -71,7 +71,7 @@
 # pragma GCC diagnostic pop
 #endif
 
-#if MOZJS_MAJOR_VERSION != 45
+#if MOZJS_MAJOR_VERSION != 52
 #error Your compiler is trying to use an incorrect major version of the \
 SpiderMonkey library. The only version that works is the one in the \
 libraries/spidermonkey/ directory, and it will not work with a typical \
@@ -79,7 +79,7 @@ system-installed version. Make sure you have got all the right files and \
 include paths.
 #endif
 
-#if MOZJS_MINOR_VERSION != 0
+#if MOZJS_MINOR_VERSION != 9
 #error Your compiler is trying to use an untested minor version of the \
 SpiderMonkey library. If you are a package maintainer, please make sure \
 to check very carefully that this version does not change the behaviour \
diff --git a/source/tools/tracelogger/tracelogger_options.sh b/source/tools/tracelogger/tracelogger_options.sh
index 2df65267c1..21613bb45a 100644
--- a/source/tools/tracelogger/tracelogger_options.sh
+++ b/source/tools/tracelogger/tracelogger_options.sh
@@ -9,13 +9,15 @@
 # The last tested version of the tool is 1c67e97e794b5039d0cae95f72ea0c76e4aa4696,
 # it can be used if more recent versions cause trouble.
 
+export TLDIR="$(dirname $(realpath $0))"
+
 # Use semicolons to separate values on Windows.
 # If that produces bogus output, you can try with commas instead.
 if [ "${OS}" = "Windows_NT" ]
 then
-  export TLLOG="Defaults;IonCompiler"
+  export TLLOG="Default;IonCompiler"
   export TLOPTIONS="EnableMainThread;EnableOffThread;EnableGraph"
 else
-  export TLLOG=Defaults,IonCompiler
+  export TLLOG=Default,IonCompiler
   export TLOPTIONS=EnableMainThread,EnableOffThread,EnableGraph
 fi