diff --git a/addons/web/static/src/js/core/error_utils.js b/addons/web/static/src/js/core/error_utils.js
index 2ccfb5cd6db..1c3e14fa01c 100644
--- a/addons/web/static/src/js/core/error_utils.js
+++ b/addons/web/static/src/js/core/error_utils.js
@@ -37,6 +37,14 @@ export function formatTraceback(error) {
 export async function annotateTraceback(error) {
   const traceback = formatTraceback(error);
   await loadJS('/web/static/lib/stacktracejs/stacktrace.js');
+  // In Firefox, the error stack generated by anonymous code (example: invalid
+  // code in a template) is not compatible with the stacktrace lib. This code
+  // corrects the stack to make it compatible with the lib stacktrace.
+  if (error.stack) {
+    const regex = / line (\d*) > (Function):(\d*)/gm;
+    const subst = `:$1`;
+    error.stack = error.stack.replace(regex, subst);
+  }
   const frames = await StackTrace.fromError(error);
   const lines = traceback.split('\n');
   if (lines[lines.length-1].trim() === "") {