diff --git a/scripts/start.mjs b/scripts/start.mjs
index d45fea4..0229d2b 100644
--- a/scripts/start.mjs
+++ b/scripts/start.mjs
@@ -61,7 +61,7 @@ function prepareDevEnv() {
         return;
       }
       if (line.includes("extensions.zotero.dataDir") && dataDir !== "") {
-        return `user_pref("extensions.zotero.dataDir", "${dataDir}");`;
+        return `user_pref("extensions.zotero.dataDir", "${dataDir.replace(/\\\\?/g, "\\\\")}");`;
       }
       return line;
     });