diff --git a/includes/class-mastodon-admin.php b/includes/class-mastodon-admin.php
index 41ca6c4..0b0dd3e 100644
--- a/includes/class-mastodon-admin.php
+++ b/includes/class-mastodon-admin.php
@@ -156,7 +156,7 @@ public function process_admin() {
 		$tab = isset( $_GET['tab'] ) ? sanitize_key( $_GET['tab'] ) : 'welcome';
 		if ( isset( $_POST['app'] ) ) {
 			$app = Mastodon_App::get_by_client_id( sanitize_text_field( wp_unslash( $_POST['app'] ) ) );
-			if ( $app ) {
+			if ( $app && ! is_wp_error( $app ) ) {
 				return $this->process_admin_app_page( $app );
 			}
 			$tab = 'registered-apps';
@@ -182,7 +182,7 @@ public function admin_page() {
 		$tab = isset( $_GET['tab'] ) ? sanitize_text_field( wp_unslash( $_GET['tab'] ) ) : 'welcome';
 		if ( isset( $_GET['app'] ) ) {
 			$app = Mastodon_App::get_by_client_id( sanitize_text_field( wp_unslash( $_GET['app'] ) ) );
-			if ( $app ) {
+			if ( $app && ! is_wp_error( $app ) ) {
 				return $this->admin_app_page( $app );
 			}
 			$tab = 'registered-apps';
diff --git a/templates/app.php b/templates/app.php
index 72c2fdd..2842b74 100644
--- a/templates/app.php
+++ b/templates/app.php
@@ -295,9 +295,6 @@ function updatePostFormatDropdown( el ) {
 		const options = postFormatSelect.querySelectorAll( 'option' );
 
 		for ( const option of options ) {
-			if ( option.value === '' ) {
-				option.textContent = option.textContent.replace( /\(.*\)/, '(' + postFormats[0].nextSibling.textContent.trim() + ')' );
-			}
 			if ( option.value === el.value ) {
 				option.disabled = ! el.checked;
 				if ( ! el.checked && postFormatSelect.value === el.value ) {
@@ -305,12 +302,15 @@ function updatePostFormatDropdown( el ) {
 				}
 			}
 		}
+		const selectedPostFormat = postFormats.length ? postFormats[0] : document.querySelector( '.post-formats input[type="checkbox"]' );
+		options[0].textContent = options[0].textContent.replace( /\(.*\)/, '(' + selectedPostFormat.nextSibling.textContent.trim() + ')' );
 	}
 
 	if ( event.target.matches( '.post-formats input[type="checkbox"]' ) ) {
 		return updatePostFormatDropdown( event.target );
 	}
 	if ( event.target.id === 'toggle_all_post_formats' ) {
+		event.preventDefault();
 		document.querySelectorAll( '.post-formats input[type="checkbox"]' ).forEach( function ( element ) {
 			element.checked = ! element.checked;
 			updatePostFormatDropdown( element );