diff --git a/test/unit/Makefile b/test/unit/Makefile
index 1702f34d2..f309935c6 100644
--- a/test/unit/Makefile
+++ b/test/unit/Makefile
@@ -1,47 +1,79 @@
 # Create temporary profile directory name.
-TEMP_PROFILE_DIR:=./test_reports/temp_profile
+TEMP_PROFILE:=./test_reports/temp_profile
 
 # These are the Firefox command line arguments.
-FIREFOX_ARGS:=-no-remote -profile $(TEMP_PROFILE_DIR)
+FIREFOX_ARGS:=-no-remote -profile $(TEMP_PROFILE)
 
 # These are the Chrome command line arguments.
-CHROME_ARGS:=--user-data-dir=$(TEMP_PROFILE_DIR) --no-first-run --disable-sync
+CHROME_ARGS:=--user-data-dir=$(TEMP_PROFILE) --no-first-run --disable-sync
 
 # Unit test uses the manifest from ref test to determine which browsers will
 # be used for running the unit tests.
 MANIFEST:=../resources/browser_manifests/browser_manifest.json
 
+# This is a helper function to separate multiple browsers to their own lines
+# for an easier sed operation.
+SPLIT_LINES:=sed 's|,|,\n|g'
+
+# This is a helper function to join multiple lines together.
+JOIN_LINES:=tr -d '\n'
+
 # Fetch the paths to browsers that are going to be used in testing.
 # For OS X the path to the binary needs to be added.
 # Add the browser arguments for each browser.
 # Create random profile directory for each browser.
-# Replace " with @@@@ so that echoing do not destroy the quotation marks.
-BROWSERS_WITH_UKNOWN_RANDOM_PROFILE_PATHS:=$(shell echo `\
+BROWSERS_PATHS:=$(shell echo `\
   sed -n 's|.*"path":\(.*\)|\1,|p' $(MANIFEST) | \
+  $(JOIN_LINES) \
+`)
+
+# The browser_manifest.json file has only the app directory for mac browsers.
+# The absolute path to the browser binary needs to be used.
+BROWSERS_PATHS_WITH_MAC_CORRECTION:=$(shell echo '$(BROWSERS_PATHS)' | \
+  $(SPLIT_LINES) | \
   sed 's|\(Aurora\.app\)|\1/Contents/MacOS/firefox-bin|' | \
   sed 's|\(Firefox.*\.app\)|\1/Contents/MacOS/firefox-bin|' | \
   sed 's|\(Google Chrome\.app\)|\1/Contents/MacOS/Google Chrome|' | \
-  sed "s|\(irefox.*\)\",|\1;$(FIREFOX_ARGS)\",|" | \
-  sed "s|\(hrome.*\)\",|\1;$(CHROME_ARGS)\",|" | \
+  $(JOIN_LINES) \
+)
+
+# Replace " with @@@@ so that echoing do not destroy the quotation marks.
+QUOTATION_MARK:=\"
+SUBSTITUTE_FOR_QUOTATION_MARK:=@@@@
+
+# Each of the browser can have their ow separate arguments.
+BROWSERS_WITH_ARGUMENTS:=$(shell echo '$(BROWSERS_PATHS_WITH_MAC_CORRECTION)' | \
+  $(SPLIT_LINES) | \
+  sed "s|\(irefox.*\)\($(QUOTATION_MARK)\),|\1;$(FIREFOX_ARGS)\2,|" | \
+  sed "s|\(hrome.*\)\($(QUOTATION_MARK)\),|\1;$(CHROME_ARGS)\2,|" | \
+  $(JOIN_LINES) \
+)
+
+# A temporary profile directory is needed for each of the browser. In this way
+# a unit test run will not disturb the main browsing session of the user. The
+# $RANDOM shell variable is used to generate non-conflicting temporary
+# directories.
+BROWSERS_WITH_UKNOWN_RANDOM_PROFILE_PATHS:=$(shell echo '$(BROWSERS_WITH_ARGUMENTS)' | \
+  $(SPLIT_LINES) | \
   sed 's|\(temp_profile\)|\1_$$(echo $$RANDOM$$RANDOM)|' | \
-  sed 's|"|@@@@|g' | \
-  tr -d '\n' \
-`)
+  sed "s|$(QUOTATION_MARK)|$(SUBSTITUTE_FOR_QUOTATION_MARK)|g" | \
+  $(JOIN_LINES) \
+)
 
 # Echo the variable so that the unknown random directories become known.
 # Replace @@@@ with " so that jsTestDriver will work properly.
 BROWSERS:=$(shell echo "$(BROWSERS_WITH_UKNOWN_RANDOM_PROFILE_PATHS)" | \
-  sed 's|@@@@|"|g' \
+  sed "s|$(SUBSTITUTE_FOR_QUOTATION_MARK)|$(QUOTATION_MARK)|g" \
 )
 
-# Split the browsers to separate lines.
 # Get the known random directories for browsers. This information will be used
-# to create the profile directories beforehand.
-# Join the separate lines back together.
-PROFILES:=$(shell echo $(BROWSERS) | \
-  sed 's|,|\n|g' | \
+# to create the profile directories beforehand. Create also the dummy temp
+# profile directory so that the mkdir command would not fail for browsers that
+# do not need it.
+PROFILES:=$(TEMP_PROFILE) $(shell echo '$(BROWSERS)' | \
+  $(SPLIT_LINES) | \
   sed -n "s|.*\(\..*_[0-9]\+\).*|\1 |p" | \
-  tr -d '\n' \
+  $(JOIN_LINES) \
 )
 
 # This is the command to invoke the unit test.
@@ -57,7 +89,13 @@ PROG:=java \
 --testOutput ./test_reports/
 
 test:
-	@echo 'Debug random profile paths: $(BROWSERS_WITH_UKNOWN_RANDOM_PROFILE_PATHS)'
+	@echo 'Debug browsers paths: $(BROWSERS_PATHS)'
+	@echo
+	@echo 'Debug browsers paths with mac correction: $(BROWSERS_PATHS_WITH_MAC_CORRECTION)'
+	@echo
+	@echo 'Debug browsers with arguments: $(BROWSERS_WITH_ARGUMENTS)'
+	@echo
+	@echo 'Debug browsers random profile paths: $(BROWSERS_WITH_UKNOWN_RANDOM_PROFILE_PATHS)'
 	@echo
 	@echo 'Debug browsers: $(BROWSERS)'
 	@echo