diff --git a/packages/docusaurus-plugin-content-blog/src/__tests__/__snapshots__/feed.test.ts.snap b/packages/docusaurus-plugin-content-blog/src/__tests__/__snapshots__/feed.test.ts.snap
index 8e600fd89a..e73f5db720 100644
--- a/packages/docusaurus-plugin-content-blog/src/__tests__/__snapshots__/feed.test.ts.snap
+++ b/packages/docusaurus-plugin-content-blog/src/__tests__/__snapshots__/feed.test.ts.snap
@@ -13,14 +13,14 @@ exports[`blogFeed atom shows feed item for each post 1`] = `
     <rights>Copyright</rights>
     <entry>
         <title type=\\"html\\"><![CDATA[MDX Blog Sample with require calls]]></title>
-        <id>MDX Blog Sample with require calls</id>
+        <id>/mdx-require-blog-post</id>
         <link href=\\"https://docusaurus.io/myBaseUrl/blog/mdx-require-blog-post\\"/>
         <updated>2021-03-06T00:00:00.000Z</updated>
         <summary type=\\"html\\"><![CDATA[Test MDX with require calls]]></summary>
     </entry>
     <entry>
         <title type=\\"html\\"><![CDATA[Full Blog Sample]]></title>
-        <id>Full Blog Sample</id>
+        <id>/mdx-blog-post</id>
         <link href=\\"https://docusaurus.io/myBaseUrl/blog/mdx-blog-post\\"/>
         <updated>2021-03-05T00:00:00.000Z</updated>
         <summary type=\\"html\\"><![CDATA[HTML Heading 1]]></summary>
@@ -49,7 +49,7 @@ exports[`blogFeed atom shows feed item for each post 1`] = `
     </entry>
     <entry>
         <title type=\\"html\\"><![CDATA[draft]]></title>
-        <id>draft</id>
+        <id>/draft</id>
         <link href=\\"https://docusaurus.io/myBaseUrl/blog/draft\\"/>
         <updated>2020-02-27T00:00:00.000Z</updated>
         <summary type=\\"html\\"><![CDATA[this post should not be published yet]]></summary>
@@ -57,13 +57,13 @@ exports[`blogFeed atom shows feed item for each post 1`] = `
     </entry>
     <entry>
         <title type=\\"html\\"><![CDATA[some heading]]></title>
-        <id>some heading</id>
+        <id>/heading-as-title</id>
         <link href=\\"https://docusaurus.io/myBaseUrl/blog/heading-as-title\\"/>
         <updated>2019-01-02T00:00:00.000Z</updated>
     </entry>
     <entry>
         <title type=\\"html\\"><![CDATA[date-matter]]></title>
-        <id>date-matter</id>
+        <id>/date-matter</id>
         <link href=\\"https://docusaurus.io/myBaseUrl/blog/date-matter\\"/>
         <updated>2019-01-01T00:00:00.000Z</updated>
         <summary type=\\"html\\"><![CDATA[date inside front matter]]></summary>
@@ -71,7 +71,7 @@ exports[`blogFeed atom shows feed item for each post 1`] = `
     </entry>
     <entry>
         <title type=\\"html\\"><![CDATA[Happy 1st Birthday Slash! (translated)]]></title>
-        <id>Happy 1st Birthday Slash! (translated)</id>
+        <id>/2018/12/14/Happy-First-Birthday-Slash</id>
         <link href=\\"https://docusaurus.io/myBaseUrl/blog/2018/12/14/Happy-First-Birthday-Slash\\"/>
         <updated>2018-12-14T00:00:00.000Z</updated>
         <summary type=\\"html\\"><![CDATA[Happy birthday! (translated)]]></summary>
@@ -100,14 +100,14 @@ exports[`blogFeed rss shows feed item for each post 1`] = `
         <item>
             <title><![CDATA[MDX Blog Sample with require calls]]></title>
             <link>https://docusaurus.io/myBaseUrl/blog/mdx-require-blog-post</link>
-            <guid>MDX Blog Sample with require calls</guid>
+            <guid>/mdx-require-blog-post</guid>
             <pubDate>Sat, 06 Mar 2021 00:00:00 GMT</pubDate>
             <description><![CDATA[Test MDX with require calls]]></description>
         </item>
         <item>
             <title><![CDATA[Full Blog Sample]]></title>
             <link>https://docusaurus.io/myBaseUrl/blog/mdx-blog-post</link>
-            <guid>Full Blog Sample</guid>
+            <guid>/mdx-blog-post</guid>
             <pubDate>Fri, 05 Mar 2021 00:00:00 GMT</pubDate>
             <description><![CDATA[HTML Heading 1]]></description>
             <content:encoded><![CDATA[<h1>HTML Heading 1</h1><h2>HTML Heading 2</h2><p>HTML Paragraph</p><div>Import DOM</div><h1>Heading 1</h1><h2>Heading 2</h2><h3>Heading 3</h3><h4>Heading 4</h4><h5>Heading 5</h5><ul><li>list1</li><li>list2</li><li>list3</li></ul><ul><li>list1</li><li>list2</li><li>list3</li></ul><p>Normal Text <em>Italics Text</em> <strong>Bold Text</strong></p><p><a href=\\"https://v2.docusaurus.io/\\">link</a>
@@ -132,7 +132,7 @@ exports[`blogFeed rss shows feed item for each post 1`] = `
         <item>
             <title><![CDATA[draft]]></title>
             <link>https://docusaurus.io/myBaseUrl/blog/draft</link>
-            <guid>draft</guid>
+            <guid>/draft</guid>
             <pubDate>Thu, 27 Feb 2020 00:00:00 GMT</pubDate>
             <description><![CDATA[this post should not be published yet]]></description>
             <content:encoded><![CDATA[<p>this post should not be published yet</p>]]></content:encoded>
@@ -140,13 +140,13 @@ exports[`blogFeed rss shows feed item for each post 1`] = `
         <item>
             <title><![CDATA[some heading]]></title>
             <link>https://docusaurus.io/myBaseUrl/blog/heading-as-title</link>
-            <guid>some heading</guid>
+            <guid>/heading-as-title</guid>
             <pubDate>Wed, 02 Jan 2019 00:00:00 GMT</pubDate>
         </item>
         <item>
             <title><![CDATA[date-matter]]></title>
             <link>https://docusaurus.io/myBaseUrl/blog/date-matter</link>
-            <guid>date-matter</guid>
+            <guid>/date-matter</guid>
             <pubDate>Tue, 01 Jan 2019 00:00:00 GMT</pubDate>
             <description><![CDATA[date inside front matter]]></description>
             <content:encoded><![CDATA[<p>date inside front matter</p>]]></content:encoded>
@@ -154,7 +154,7 @@ exports[`blogFeed rss shows feed item for each post 1`] = `
         <item>
             <title><![CDATA[Happy 1st Birthday Slash! (translated)]]></title>
             <link>https://docusaurus.io/myBaseUrl/blog/2018/12/14/Happy-First-Birthday-Slash</link>
-            <guid>Happy 1st Birthday Slash! (translated)</guid>
+            <guid>/2018/12/14/Happy-First-Birthday-Slash</guid>
             <pubDate>Fri, 14 Dec 2018 00:00:00 GMT</pubDate>
             <description><![CDATA[Happy birthday! (translated)]]></description>
             <content:encoded><![CDATA[<p>Happy birthday! (translated)</p>]]></content:encoded>
diff --git a/packages/docusaurus-plugin-content-blog/src/blogUtils.ts b/packages/docusaurus-plugin-content-blog/src/blogUtils.ts
index d7372ad9a7..167bc7bbce 100644
--- a/packages/docusaurus-plugin-content-blog/src/blogUtils.ts
+++ b/packages/docusaurus-plugin-content-blog/src/blogUtils.ts
@@ -219,7 +219,7 @@ async function processBlogSourceFile(
   const authors = getBlogPostAuthors({authorsMap, frontMatter});
 
   return {
-    id: frontMatter.slug ?? title,
+    id: slug,
     metadata: {
       permalink,
       editUrl: getBlogEditUrl(),
diff --git a/website/_dogfooding/_blog tests/2021-09-13-dup-title.md b/website/_dogfooding/_blog tests/2021-09-13-dup-title.md
new file mode 100644
index 0000000000..82d4aea512
--- /dev/null
+++ b/website/_dogfooding/_blog tests/2021-09-13-dup-title.md	
@@ -0,0 +1,3 @@
+# Post with duplicate title
+
+See https://github.com/facebook/docusaurus/issues/6059. This one and [2021-11-13-dup-title.md](./2021-11-13-dup-title.md) should both show up.
diff --git a/website/_dogfooding/_blog tests/2021-11-13-dup-title.md b/website/_dogfooding/_blog tests/2021-11-13-dup-title.md
new file mode 100644
index 0000000000..69d9b04f66
--- /dev/null
+++ b/website/_dogfooding/_blog tests/2021-11-13-dup-title.md	
@@ -0,0 +1,3 @@
+# Post with duplicate title
+
+I hope I'm still here