diff --git a/devtools/client/netmonitor/test/browser_net_curl-utils.js b/devtools/client/netmonitor/test/browser_net_curl-utils.js
index b4b2c175ee8..a1273afb7db 100644
--- a/devtools/client/netmonitor/test/browser_net_curl-utils.js
+++ b/devtools/client/netmonitor/test/browser_net_curl-utils.js
@@ -326,10 +326,10 @@ function testEscapeStringWin() {
     "Percent signs should be escaped."
   );
 
-  const backslashes = "\\A simple string\\";
+  const backslashes = " - \\A simple string\\ - ";
   is(
     CurlUtils.escapeStringWin(backslashes),
-    '^\"^\\A simple string^\\^\"',
+    '^\" - ^\\^\\A simple string^\\^\\ - ^\"',
     "Backslashes should be escaped."
   );
 
diff --git a/devtools/client/shared/curl.js b/devtools/client/shared/curl.js
index d86e9df5a5d..ccb61c4259c 100644
--- a/devtools/client/shared/curl.js
+++ b/devtools/client/shared/curl.js
@@ -458,6 +458,9 @@ const CurlUtils = {
     return (
       encapsChars +
       str
+        // Replace all the \ (used as the escape character in the next replace) with \\
+        .replace(/\\/g, "\\\\")
+
         // Replace all " with \" to ensure the first parser does not remove it.
         .replace(/"/g, '\\"')
 

diff --git a/devtools/client/netmonitor/test/browser_net_curl-utils.js b/devtools/client/netmonitor/test/browser_net_curl-utils.js
index b4b2c175ee8..a1273afb7db 100644
--- a/devtools/client/netmonitor/test/browser_net_curl-utils.js
+++ b/devtools/client/netmonitor/test/browser_net_curl-utils.js
@@ -326,10 +326,10 @@ function testEscapeStringWin() {
     "Percent signs should be escaped."
   );
 
-  const backslashes = "\\A simple string\\";
+  const backslashes = " - \\A simple string\\ - ";
   is(
     CurlUtils.escapeStringWin(backslashes),
-    '^\"^\\A simple string^\\^\"',
+    '^\" - ^\\^\\A simple string^\\^\\ - ^\"',
     "Backslashes should be escaped."
   );