apps/wpcom-block-editor/src/calypso/iframe-bridge-server.js
function openLinksInParentFrame() {
	const viewPostLinkSelectors = [
		'.components-notice-list .is-success .components-notice__action.is-link', // View Post link in success notice
		'.post-publish-panel__postpublish .components-panel__body.is-opened a', // Post title link in publish panel
		'.components-panel__body.is-opened .post-publish-panel__postpublish-buttons a.components-button', // View Post button in publish panel
	].join( ',' );
	$( '#editor' ).on( 'click', viewPostLinkSelectors, e => {
		e.preventDefault();
		window.open( e.target.href, '_top' );
	} );

	if ( calypsoifyGutenberg.manageReusableBlocksUrl ) {
		const manageReusableBlocksLinkSelectors = [
			'.editor-inserter__manage-reusable-blocks', // Link in the Blocks Inserter
			'a.components-menu-item__button[href*="post_type=wp_block"]', // Link in the More Menu
		].join( ',' );
		$( '#editor' ).on( 'click', manageReusableBlocksLinkSelectors, e => {
			e.preventDefault();
			window.open( calypsoifyGutenberg.manageReusableBlocksUrl, '_top' );
		} );
	}
}
function openLinksInParentFrame() {
	const viewPostLinkSelectors = [
		'.components-notice-list .is-success .components-notice__action.is-link', // View Post link in success notice
		'.post-publish-panel__postpublish .components-panel__body.is-opened a', // Post title link in publish panel
		'.components-panel__body.is-opened .post-publish-panel__postpublish-buttons a.components-button', // View Post button in publish panel
	].join( ',' );
	$( '#editor' ).on( 'click', viewPostLinkSelectors, e => {
		e.preventDefault();
		window.open( e.target.href, '_top' );
	} );

	if ( calypsoifyGutenberg.manageReusableBlocksUrl ) {
		const manageReusableBlocksLinkSelectors = [
			'.editor-inserter__manage-reusable-blocks', // Link in the Blocks Inserter
			'a.components-menu-item__button[href*="post_type=wp_block"]', // Link in the More Menu
		].join( ',' );
		$( '#editor' ).on( 'click', manageReusableBlocksLinkSelectors, e => {
			e.preventDefault();
			window.open( calypsoifyGutenberg.manageReusableBlocksUrl, '_top' );
		} );
	}
}
Modify links in order to open them in parent window and not in a child iframe.