Theme: Treat the block-based theme as a FSE theme

client/my-sites/themes/is-full-site-editing-theme.ts

@@ -1,6 +1,10 @@
 import { Theme } from 'calypso/types';
 
 export function isFullSiteEditingTheme( theme: Theme | null ): boolean {
+	if ( theme?.block_theme ) {
+		return true;
+	}
+
 	const features = theme?.taxonomies?.theme_feature;
 	return features?.some( ( feature ) => feature.slug === 'full-site-editing' ) ?? false;
 }

client/state/themes/selectors/is-full-site-editing-theme.ts

@@ -20,6 +20,10 @@ export function isFullSiteEditingTheme(
 		return false;
 	}
 
+	if ( theme.block_theme ) {
+		return true;
+	}
+
 	const themeFeatures = getThemeTaxonomySlugs( theme, 'theme_feature' );
 
 	return themeFeatures.includes( 'full-site-editing' );

client/types.ts

@@ -24,6 +24,7 @@ export interface Theme {
 	author: string;
 	author_uri: string;
 	cost: ThemeCost;
+	block_theme?: boolean;
 	date_launched: string;
 	date_updated: string;
 	demo_uri?: string;