diff --git a/packages/block-library/src/post-comments-count/block.json b/packages/block-library/src/post-comments-count/block.json
index 796e6e3830236c..2c41f4d4f4c400 100644
--- a/packages/block-library/src/post-comments-count/block.json
+++ b/packages/block-library/src/post-comments-count/block.json
@@ -26,6 +26,12 @@
 			"margin": true,
 			"padding": true
 		},
+		"__experimentalBorder": {
+			"radius": true,
+			"color": true,
+			"width": true,
+			"style": true
+		},
 		"typography": {
 			"fontSize": true,
 			"lineHeight": true,
diff --git a/packages/block-library/src/post-template/editor.scss b/packages/block-library/src/post-template/editor.scss
index 1adeee4b1c13e1..7b426b0f3d37a5 100644
--- a/packages/block-library/src/post-template/editor.scss
+++ b/packages/block-library/src/post-template/editor.scss
@@ -3,6 +3,5 @@
 		padding-left: 0;
 		margin-left: 0;
 		list-style: none;
-		box-sizing: border-box;
 	}
 }
diff --git a/packages/block-library/src/post-template/style.scss b/packages/block-library/src/post-template/style.scss
index 7dce26dcd6a26b..e6896f2db024a8 100644
--- a/packages/block-library/src/post-template/style.scss
+++ b/packages/block-library/src/post-template/style.scss
@@ -4,6 +4,7 @@
 	max-width: 100%;
 	list-style: none;
 	padding: 0;
+	// This block has customizable padding, border-box makes that more predictable.
 	box-sizing: border-box;
 
 	// These rules no longer apply but should be kept for backwards compatibility.