diff --git a/src/node/proxy.ts b/src/node/proxy.ts
index da430f5b3a15..35fd5d81a4d0 100644
--- a/src/node/proxy.ts
+++ b/src/node/proxy.ts
@@ -9,6 +9,8 @@ proxy.on("error", (error, _, res) => {
 })
 
 // Intercept the response to rewrite absolute redirects against the base path.
+// Is disabled when the request has no base path which means --proxy-path-passthrough has
+// been enabled.
 proxy.on("proxyRes", (res, req) => {
   if (res.headers.location && res.headers.location.startsWith("/") && (req as any).base) {
     res.headers.location = (req as any).base + res.headers.location
diff --git a/src/node/routes/pathProxy.ts b/src/node/routes/pathProxy.ts
index 9554a006d290..6a6b9d29c23d 100644
--- a/src/node/routes/pathProxy.ts
+++ b/src/node/routes/pathProxy.ts
@@ -28,8 +28,10 @@ router.all("/(:port)(/*)?", (req, res) => {
     throw new HttpError("Unauthorized", HttpCode.Unauthorized)
   }
 
-  // Absolute redirects need to be based on the subpath when rewriting.
-  ;(req as any).base = `${req.baseUrl}/${req.params.port}`
+  if (!req.args["proxy-path-passthrough"]) {
+    // Absolute redirects need to be based on the subpath when rewriting.
+    ;(req as any).base = `${req.baseUrl}/${req.params.port}`
+  }
 
   proxy.web(req, res, {
     ignorePath: true,