diff --git a/lib/html_to_markdown.rb b/lib/html_to_markdown.rb
index df8084ae4c..9e18269c66 100644
--- a/lib/html_to_markdown.rb
+++ b/lib/html_to_markdown.rb
@@ -143,9 +143,14 @@ class HtmlToMarkdown
   end
 
   def visit_a(node)
-    @stack[-1].markdown << "["
-    traverse(node)
-    @stack[-1].markdown << "](#{node["href"]})"
+    href = node["href"]
+    if href.present? && (href.start_with?("http") || href.start_with?("www."))
+      @stack[-1].markdown << "["
+      traverse(node)
+      @stack[-1].markdown << "](#{href})"
+    else
+      traverse(node)
+    end
   end
 
   def visit_tt(node)
diff --git a/spec/components/html_to_markdown_spec.rb b/spec/components/html_to_markdown_spec.rb
index f2344e5839..43651536e3 100644
--- a/spec/components/html_to_markdown_spec.rb
+++ b/spec/components/html_to_markdown_spec.rb
@@ -31,6 +31,12 @@ describe HtmlToMarkdown do
     expect(html_to_markdown(%Q{<a href="https://www.discourse.org">Discourse</a>})).to eq("[Discourse](https://www.discourse.org)")
   end
 
+  it "removes empty & invalid <a>" do
+    expect(html_to_markdown(%Q{<a>Discourse</a>})).to eq("Discourse")
+    expect(html_to_markdown(%Q{<a href="">Discourse</a>})).to eq("Discourse")
+    expect(html_to_markdown(%Q{<a href="foo.bar">Discourse</a>})).to eq("Discourse")
+  end
+
   HTML_WITH_IMG ||= %Q{<img src="https://www.discourse.org/logo.svg" alt="Discourse Logo">}
 
   it "converts <img>" do