diff --git a/scripts/extra_script.py b/scripts/extra_script.py
index d934023..4a1c118 100644
--- a/scripts/extra_script.py
+++ b/scripts/extra_script.py
@@ -29,9 +29,10 @@ def process_directory(input_dir, output_dir):
 
 # Build web interface before building FS
 def before_buildfs(source, target, env):
-    env.Execute("cd data && yarn && yarn postinstall && PUBLIC_BASE_URL=\"\" yarn build")
+    env.Execute("cd data && yarn && yarn postinstall && yarn build")
     input_directory = 'data/dist'
     output_directory = 'data/build_gz'
     process_directory(input_directory, output_directory)
 
+os.environ["PUBLIC_BASE_URL"] = ""
 env.AddPreAction("$BUILD_DIR/littlefs.bin", before_buildfs)