diff --git a/packages/block-library/src/details/edit.js b/packages/block-library/src/details/edit.js
index 81e4d7a52056a7..0d1d675893900f 100644
--- a/packages/block-library/src/details/edit.js
+++ b/packages/block-library/src/details/edit.js
@@ -72,7 +72,6 @@ function DetailsEdit( { attributes, setAttributes, clientId } ) {
 						onChange={ ( newSummary ) =>
 							setAttributes( { summary: newSummary } )
 						}
-						multiline={ false }
 					/>
 				</summary>
 				{ innerBlocksProps.children }
diff --git a/packages/block-library/src/post-author/edit.js b/packages/block-library/src/post-author/edit.js
index 4ee353fdd9bdc0..05797fcc8250a1 100644
--- a/packages/block-library/src/post-author/edit.js
+++ b/packages/block-library/src/post-author/edit.js
@@ -196,7 +196,6 @@ function PostAuthorEdit( {
 					{ ( ! RichText.isEmpty( byline ) || isSelected ) && (
 						<RichText
 							className="wp-block-post-author__byline"
-							multiline={ false }
 							aria-label={ __( 'Post author byline text' ) }
 							placeholder={ __( 'Write byline…' ) }
 							value={ byline }
diff --git a/packages/block-library/src/post-terms/edit.js b/packages/block-library/src/post-terms/edit.js
index 188a8d22f2f8e2..b5eb0bb9e3bfb6 100644
--- a/packages/block-library/src/post-terms/edit.js
+++ b/packages/block-library/src/post-terms/edit.js
@@ -97,7 +97,6 @@ export default function PostTermsEdit( {
 					<RichText
 						allowedFormats={ ALLOWED_FORMATS }
 						className="wp-block-post-terms__prefix"
-						multiline={ false }
 						aria-label={ __( 'Prefix' ) }
 						placeholder={ __( 'Prefix' ) + ' ' }
 						value={ prefix }
@@ -141,7 +140,6 @@ export default function PostTermsEdit( {
 					<RichText
 						allowedFormats={ ALLOWED_FORMATS }
 						className="wp-block-post-terms__suffix"
-						multiline={ false }
 						aria-label={ __( 'Suffix' ) }
 						placeholder={ ' ' + __( 'Suffix' ) }
 						value={ suffix }