diff --git a/packages/docusaurus-theme-classic/src/theme/DocSidebar/index.tsx b/packages/docusaurus-theme-classic/src/theme/DocSidebar/index.tsx
index 19e3fa9848fa..c78a6a99119e 100644
--- a/packages/docusaurus-theme-classic/src/theme/DocSidebar/index.tsx
+++ b/packages/docusaurus-theme-classic/src/theme/DocSidebar/index.tsx
@@ -157,6 +157,7 @@ function DocSidebarItemLink({
       <Link
         className={clsx('menu__link', {
           'menu__link--active': isActive,
+          [styles.menuLinkExternal]: !isInternalUrl(href),
         })}
         to={href}
         {...(isInternalUrl(href) && {
diff --git a/packages/docusaurus-theme-classic/src/theme/DocSidebar/styles.module.css b/packages/docusaurus-theme-classic/src/theme/DocSidebar/styles.module.css
index 721e212c22b4..a1de555cdab8 100644
--- a/packages/docusaurus-theme-classic/src/theme/DocSidebar/styles.module.css
+++ b/packages/docusaurus-theme-classic/src/theme/DocSidebar/styles.module.css
@@ -119,5 +119,19 @@
 }
 
 :global(.menu__list-item--collapsed) :global(.menu__list) {
-  height: 0px !important;
+  height: 0 !important;
+}
+
+.menuLinkExternal {
+  align-items: center;
+}
+.menuLinkExternal:after {
+  content: '';
+  height: 1.15rem;
+  width: 1.15rem;
+  min-width: 1.15rem;
+  margin: 0 auto 0 3%;
+  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24'%3E%3Cpath fill='rgba(0,0,0,0.5)' d='M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z'/%3E%3C/svg%3E")
+    no-repeat;
+  filter: var(--ifm-menu-link-sublist-icon-filter);
 }