diff --git a/.github/workflows/autobuild.yml b/.github/workflows/autobuild.yml
index 01e5aecc..74b5d0f6 100644
--- a/.github/workflows/autobuild.yml
+++ b/.github/workflows/autobuild.yml
@@ -863,7 +863,7 @@ jobs:
       - name: Set up Emscripten SDK
         uses: mymindstorm/setup-emsdk@v14
         with:
-          version: 3.1.46
+          version: 4.0.6
 
       - id: short-sha
         name: Get Git commit hash
@@ -906,33 +906,30 @@ jobs:
           mkdir ${{ runner.temp }}/dist
           cd build
           CLICOLOR_FORCE=1 ninja -v
-          mv mkxp-z_libretro.bc ${{ runner.temp }}
+          mv mkxp-z_libretro.a ${{ runner.temp }}
 
       - name: Build frontend
         run: |
           cd ${{ runner.temp }}
           tag_name=$(curl -s https://api.github.com/repos/libretro/RetroArch/releases/latest | jq -r '.tag_name')
-          git clone https://github.com/libretro/RetroArch retroarch --depth 1 -b $tag_name
-          mv mkxp-z_libretro.bc retroarch/libretro_emscripten.bc
+          if [ $tag_name = 'v1.20.0' ]
+          then
+            # Use nightly instead of 1.20.0 for now
+            git clone https://github.com/libretro/RetroArch retroarch --depth 1 -b master
+          else
+            git clone https://github.com/libretro/RetroArch retroarch --depth 1 -b $tag_name
+          fi
+          mv mkxp-z_libretro.a retroarch/libretro_emscripten.a
           cd retroarch
           if [ '${{ matrix.threading }}' = 'threaded' ]
           then
-            if [ $tag_name = 'v1.20.0' ]
-            then
-              threading_flags='PTHREAD=1'
-            else
-              threading_flags='HAVE_THREADS=1 HAVE_AUDIOWORKLET=1 PROXY_TO_PTHREAD=1 HAVE_WASMFS=1 HAVE_EXTRA_WASMFS=1'
-            fi
+            threading_flags='HAVE_THREADS=1 HAVE_AUDIOWORKLET=1 PROXY_TO_PTHREAD=1 HAVE_WASMFS=1 HAVE_EXTRA_WASMFS=1'
           else
             threading_flags=
           fi
           CLICOLOR_FORCE=1 emmake make -f Makefile.emscripten LIBRETRO=mkxp-z $threading_flags
           mv mkxp-z_libretro.wasm ${{ runner.temp }}/dist
           mv mkxp-z_libretro.js ${{ runner.temp }}/dist
-          if [ '${{ matrix.threading }}' = 'threaded' ]
-          then
-            mv mkxp-z_libretro.worker.js ${{ runner.temp }}/dist
-          fi
 
       - name: Upload artifact
         uses: actions/upload-artifact@v4
diff --git a/meson.build b/meson.build
index 889ec5d7..3893d215 100644
--- a/meson.build
+++ b/meson.build
@@ -9,6 +9,7 @@ compilers = {'c': meson.get_compiler('c'), 'cpp': meson.get_compiler('cpp')}
 is_libretro = get_option('libretro')
 is_emscripten = host_system == 'emscripten'
 core_is_static = is_libretro and (is_emscripten or host_system == 'bare' or host_system == 'none')
+core_is_relocatable_object = is_libretro and is_emscripten and compilers['c'].version().version_compare('<3.1.52')
 is_vita = core_is_static and host_cpu_family == 'arm' and compilers['c'].has_header_symbol('sys/config.h', '__vita__')
 is_devkitarm = core_is_static and host_cpu_family == 'arm' and not is_vita
 is_devkitppc = core_is_static and host_cpu_family == 'ppc'
@@ -493,7 +494,7 @@ if is_libretro
         global_dependencies_processed = global_dependencies
     endif
 
-    if is_emscripten
+    if core_is_relocatable_object
         libretro_target_type = 'executable' # Actually a relocatable object; we just pass 'executable' as the target type to get Meson to use the correct commands
     elif core_is_static
         libretro_target_type = 'static_library'
@@ -504,7 +505,7 @@ if is_libretro
     libretro = build_target(
         meson.project_name() + '_libretro',
         name_prefix: '',
-        name_suffix: is_emscripten ? 'bc' : [],
+        name_suffix: core_is_relocatable_object ? 'bc' : [],
         target_type: libretro_target_type,
         dependencies: global_dependencies_processed,
         c_args: global_args,
diff --git a/meson_options.txt b/meson_options.txt
index b0b50b06..b5e8d3d7 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -25,4 +25,4 @@ option('gfx_backend', type: 'combo', value: 'gl', choices: ['gl', 'gles'], descr
 option('libretro', type: 'boolean', value: false, description: 'Build a libretro core instead of an executable')
 option('libretro_stage1_path', type: 'string', value: 'libretro/build/libretro-stage1', description: 'Path to libretro-stage1 for libretro builds')
 option('ruby_lto', type: 'boolean', value: false, description: 'Enable link-time optimization for libruby in libretro builds, even if link-time optimization is disabled for everything else')
-option('emscripten_threaded', type: 'boolean', value: true, description: 'Enable multithreading support in libretro builds')
+option('emscripten_threaded', type: 'boolean', value: true, description: 'Enable multithreading support in libretro Emscripten builds')