Try.

Bravo Yeung · Bravo Yeung · commit 41644144e244 · 2020-10-23T08:40:49.000+08:00
diff --git a/github_io_sitemap.txt b/github_io_sitemap.txt
@@ -5,7 +5,7 @@ layout: null
 {{ site.url | replace: "www.geekzl.com", "wpfgeek.github.io" }}{{ post.url }}
 {% endfor %}
 {% for page in site.pages %}
-{% unless page.url.startswith('/20') == false %}
+{% unless page.url.startswith('/20') %}
 {{ site.url | replace: "www.geekzl.com", "wpfgeek.github.io" }}{{ page.url | remove: "index.html" }}
 {% endunless %}
 {% endfor %}
