diff --git a/packages/docusaurus-utils/src/__tests__/index.test.ts b/packages/docusaurus-utils/src/__tests__/index.test.ts
index fd251e3205..a47fc0f15e 100644
--- a/packages/docusaurus-utils/src/__tests__/index.test.ts
+++ b/packages/docusaurus-utils/src/__tests__/index.test.ts
@@ -250,6 +250,10 @@ describe('load utils', () => {
         input: ['/test/', '/docs', 'ro', 'doc1'],
         output: '/test/docs/ro/doc1',
       },
+      {
+        input: ['/test/', '/', 'ro', 'doc1'],
+        output: '/test/ro/doc1',
+      },
       {
         input: ['', '/', 'ko', 'hello'],
         output: '/ko/hello',
diff --git a/packages/docusaurus-utils/src/index.ts b/packages/docusaurus-utils/src/index.ts
index a8a457ab1f..2309c680be 100644
--- a/packages/docusaurus-utils/src/index.ts
+++ b/packages/docusaurus-utils/src/index.ts
@@ -253,8 +253,8 @@ export function normalizeUrl(rawUrls: string[]): string {
   const parts = str.split('?');
   str = parts.shift() + (parts.length > 0 ? '?' : '') + parts.join('&');
 
-  // Dedupe forward slashes.
-  str = str.replace(/^\/+/, '/');
+  // Dedupe forward slashes in the entire path, avoiding protocol slashes.
+  str = str.replace(/([^:]\/)\/+/g, '$1');
 
   return str;
 }