diff --git a/packages/editor/src/components/post-format/index.js b/packages/editor/src/components/post-format/index.js
index 34e86a15b9d7f..8f7423239600f 100644
--- a/packages/editor/src/components/post-format/index.js
+++ b/packages/editor/src/components/post-format/index.js
@@ -100,8 +100,7 @@ export default function PostFormat() {
 				{ suggestion && suggestion.id !== postFormat && (
 					<p className="editor-post-format__suggestion">
 						<Button
-							// TODO: Switch to `true` (40px size) if possible
-							__next40pxDefaultSize={ false }
+							__next40pxDefaultSize
 							variant="link"
 							onClick={ () =>
 								onUpdatePostFormat( suggestion.id )
diff --git a/packages/editor/src/components/post-last-revision/index.js b/packages/editor/src/components/post-last-revision/index.js
index b47ddb3acddd5..c0ce37198c951 100644
--- a/packages/editor/src/components/post-last-revision/index.js
+++ b/packages/editor/src/components/post-last-revision/index.js
@@ -36,8 +36,7 @@ function PostLastRevision() {
 	return (
 		<PostLastRevisionCheck>
 			<Button
-				// TODO: Switch to `true` (40px size) if possible
-				__next40pxDefaultSize={ false }
+				__next40pxDefaultSize
 				href={ addQueryArgs( 'revision.php', {
 					revision: lastRevisionId,
 				} ) }
diff --git a/packages/editor/src/components/post-locked-modal/index.js b/packages/editor/src/components/post-locked-modal/index.js
index afb0d48e1a133..7bfa2d23fd980 100644
--- a/packages/editor/src/components/post-locked-modal/index.js
+++ b/packages/editor/src/components/post-locked-modal/index.js
@@ -257,8 +257,7 @@ export default function PostLockedModal() {
 					>
 						{ ! isTakeover && (
 							<Button
-								// TODO: Switch to `true` (40px size) if possible
-								__next40pxDefaultSize={ false }
+								__next40pxDefaultSize
 								variant="tertiary"
 								href={ unlockUrl }
 							>
@@ -266,8 +265,7 @@ export default function PostLockedModal() {
 							</Button>
 						) }
 						<Button
-							// TODO: Switch to `true` (40px size) if possible
-							__next40pxDefaultSize={ false }
+							__next40pxDefaultSize
 							variant="primary"
 							href={ allPostsUrl }
 						>
diff --git a/packages/editor/src/components/post-publish-panel/index.js b/packages/editor/src/components/post-publish-panel/index.js
index 3e411e91db472..f0e9a55eae060 100644
--- a/packages/editor/src/components/post-publish-panel/index.js
+++ b/packages/editor/src/components/post-publish-panel/index.js
@@ -78,8 +78,7 @@ export class PostPublishPanel extends Component {
 				<div className="editor-post-publish-panel__header">
 					{ isPostPublish ? (
 						<Button
-							// TODO: Switch to `true` (40px size) if possible
-							__next40pxDefaultSize={ false }
+							size="compact"
 							onClick={ onClose }
 							icon={ closeSmall }
 							label={ __( 'Close panel' ) }
diff --git a/packages/editor/src/components/post-publish-panel/maybe-post-format-panel.js b/packages/editor/src/components/post-publish-panel/maybe-post-format-panel.js
index 6320390d9da5c..a81168808f1af 100644
--- a/packages/editor/src/components/post-publish-panel/maybe-post-format-panel.js
+++ b/packages/editor/src/components/post-publish-panel/maybe-post-format-panel.js
@@ -25,8 +25,7 @@ const PostFormatSuggestion = ( {
 	onUpdatePostFormat,
 } ) => (
 	<Button
-		// TODO: Switch to `true` (40px size) if possible
-		__next40pxDefaultSize={ false }
+		__next40pxDefaultSize
 		variant="link"
 		onClick={ () => onUpdatePostFormat( suggestedPostFormat ) }
 	>
diff --git a/packages/editor/src/components/post-publish-panel/maybe-upload-media.js b/packages/editor/src/components/post-publish-panel/maybe-upload-media.js
index b090e25cd4dbf..491173d439efe 100644
--- a/packages/editor/src/components/post-publish-panel/maybe-upload-media.js
+++ b/packages/editor/src/components/post-publish-panel/maybe-upload-media.js
@@ -155,8 +155,7 @@ export default function PostFormatPanel() {
 					<Spinner />
 				) : (
 					<Button
-						// TODO: Switch to `true` (40px size) if possible
-						__next40pxDefaultSize={ false }
+						__next40pxDefaultSize
 						variant="primary"
 						onClick={ uploadImages }
 					>
diff --git a/packages/editor/src/components/post-publish-panel/test/__snapshots__/index.js.snap b/packages/editor/src/components/post-publish-panel/test/__snapshots__/index.js.snap
index 9331376d7f9c3..1dd75fffaa7b6 100644
--- a/packages/editor/src/components/post-publish-panel/test/__snapshots__/index.js.snap
+++ b/packages/editor/src/components/post-publish-panel/test/__snapshots__/index.js.snap
@@ -60,7 +60,7 @@ exports[`PostPublishPanel should render the post-publish panel if the post is pu
     >
       <button
         aria-label="Close panel"
-        class="components-button has-icon"
+        class="components-button is-compact has-icon"
         type="button"
       >
         <svg
@@ -252,7 +252,7 @@ exports[`PostPublishPanel should render the post-publish panel if the post is sc
     >
       <button
         aria-label="Close panel"
-        class="components-button has-icon"
+        class="components-button is-compact has-icon"
         type="button"
       >
         <svg