Fix mac cfg

emsdk.py

diff --git a/emsdk.py b/emsdk.py
index de19c82..a38e7a6 100644
--- a/emsdk.py
+++ b/emsdk.py
@@ -1307,6 +1307,7 @@
   exe_dir = os.path.join(root, 'Contents', 'MacOS') if MACOS else root
   firefox_exe = os.path.join(exe_dir, exe_suffix('firefox'))
   if os.path.isfile(firefox_exe):
+    print(firefox_exe + ' is already installed, skipping..')
     return True
 
   filename = scraper.download()

emsdk_manifest.json

diff --git a/emsdk_manifest.json b/emsdk_manifest.json
index 7e9dc8d..1e468de 100644
--- a/emsdk_manifest.json
+++ b/emsdk_manifest.json
@@ -525,8 +525,8 @@
     "git_branch": "dummy field, to instruct emsdk to attempt to reinstall this tool even if it is installed, to check for new version",
     "activated_cfg": "EMTEST_BROWSER=%actual_installation_dir%/firefox%.exe%",
     "activated_env": "EMTEST_BROWSER=%actual_installation_dir%/firefox%.exe%",
-    "mac_activated_cfg": "EMTEST_BROWSER=%installation_dir%/Contents/MacOS/firefox%.exe%",
-    "mac_activated_env": "EMTEST_BROWSER=%installation_dir%/Contents/MacOS/firefox%.exe%",
+    "mac_activated_cfg": "EMTEST_BROWSER=%actual_installation_dir%/Contents/MacOS/firefox%.exe%",
+    "mac_activated_env": "EMTEST_BROWSER=%actual_installation_dir%/Contents/MacOS/firefox%.exe%",
     "custom_install_script": "mozdownload_firefox",
     "custom_is_installed_script": "is_firefox_installed"
   },
@@ -538,8 +538,8 @@
     "git_branch": "dummy field, to instruct emsdk to attempt to reinstall this tool even if it is installed, to check for new version",
     "activated_cfg": "EMTEST_BROWSER=%actual_installation_dir%/firefox%.exe%",
     "activated_env": "EMTEST_BROWSER=%actual_installation_dir%/firefox%.exe%",
-    "mac_activated_cfg": "EMTEST_BROWSER=%installation_dir%/Contents/MacOS/firefox%.exe%",
-    "mac_activated_env": "EMTEST_BROWSER=%installation_dir%/Contents/MacOS/firefox%.exe%",
+    "mac_activated_cfg": "EMTEST_BROWSER=%actual_installation_dir%/Contents/MacOS/firefox%.exe%",
+    "mac_activated_env": "EMTEST_BROWSER=%actual_installation_dir%/Contents/MacOS/firefox%.exe%",
     "custom_install_script": "mozdownload_firefox",
     "custom_is_installed_script": "is_firefox_installed"
   },
@@ -551,8 +551,8 @@
     "git_branch": "dummy field, to instruct emsdk to attempt to reinstall this tool even if it is installed, to check for new version",
     "activated_cfg": "EMTEST_BROWSER=%actual_installation_dir%/firefox%.exe%",
     "activated_env": "EMTEST_BROWSER=%actual_installation_dir%/firefox%.exe%",
-    "mac_activated_cfg": "EMTEST_BROWSER=%installation_dir%/Contents/MacOS/firefox%.exe%",
-    "mac_activated_env": "EMTEST_BROWSER=%installation_dir%/Contents/MacOS/firefox%.exe%",
+    "mac_activated_cfg": "EMTEST_BROWSER=%actual_installation_dir%/Contents/MacOS/firefox%.exe%",
+    "mac_activated_env": "EMTEST_BROWSER=%actual_installation_dir%/Contents/MacOS/firefox%.exe%",
     "custom_install_script": "mozdownload_firefox",
     "custom_is_installed_script": "is_firefox_installed"
   },