diff --git a/application/basilisk/confvars.sh b/application/basilisk/confvars.sh
index 18ac2bdb3c..6451eabb4f 100644
--- a/application/basilisk/confvars.sh
+++ b/application/basilisk/confvars.sh
@@ -66,3 +66,9 @@ if test "$OS_ARCH" = "WINNT" -o \
         "$OS_ARCH" = "Darwin"; then
   MOZ_CAN_DRAW_IN_TITLEBAR=1
 fi
+
+# Set the chrome packing format
+# Possible values are omni, jar, and flat
+# Currently, only omni and flat are supported
+MOZ_CHROME_FILE_FORMAT=omni
+JAR_COMPRESSION=brotli
diff --git a/application/palemoon/confvars.sh b/application/palemoon/confvars.sh
index 9da99d1e20..b77423ee00 100644
--- a/application/palemoon/confvars.sh
+++ b/application/palemoon/confvars.sh
@@ -93,6 +93,7 @@ fi
 # Possible values are omni, jar, and flat
 # Currently, only omni and flat are supported
 MOZ_CHROME_FILE_FORMAT=omni
+JAR_COMPRESSION=brotli
 
 # Set the default top-level extensions
 MOZ_EXTENSIONS_DEFAULT=" gio"