diff --git a/src/wp-admin/js/customize-controls.js b/src/wp-admin/js/customize-controls.js
index d9db2e600a..c7b5905f43 100644
--- a/src/wp-admin/js/customize-controls.js
+++ b/src/wp-admin/js/customize-controls.js
@@ -2567,7 +2567,7 @@
 
 			// Temporary special function since supplying SFTP credentials does not work yet. See #42184.
 			function disableInstallButtons() {
-				return disableSwitchButtons() || true === api.settings.theme._filesystemCredentialsNeeded;
+				return disableSwitchButtons() || false === api.settings.theme._canInstall || true === api.settings.theme._filesystemCredentialsNeeded;
 			}
 
 			section.overlay.find( 'button.preview, button.preview-theme' ).toggleClass( 'disabled', disableSwitchButtons() );
@@ -3064,7 +3064,7 @@
 			api.Panel.prototype.attachEvents.apply( panel );
 
 			// Temporary since supplying SFTP credentials does not work yet. See #42184
-			if ( api.settings.theme._filesystemCredentialsNeeded ) {
+			if ( api.settings.theme._canInstall && api.settings.theme._filesystemCredentialsNeeded ) {
 				panel.notifications.add( new api.Notification( 'theme_install_unavailable', {
 					message: api.l10n.themeInstallUnavailable,
 					type: 'info',
@@ -5092,7 +5092,7 @@
 
 			// Temporary special function since supplying SFTP credentials does not work yet. See #42184.
 			function disableInstallButtons() {
-				return disableSwitchButtons() || true === api.settings.theme._filesystemCredentialsNeeded;
+				return disableSwitchButtons() || false === api.settings.theme._canInstall || true === api.settings.theme._filesystemCredentialsNeeded;
 			}
 			function updateButtons() {
 				control.container.find( 'button.preview, button.preview-theme' ).toggleClass( 'disabled', disableSwitchButtons() );
diff --git a/src/wp-includes/class-wp-customize-manager.php b/src/wp-includes/class-wp-customize-manager.php
index fe22d87a06..c453fc0841 100644
--- a/src/wp-includes/class-wp-customize-manager.php
+++ b/src/wp-includes/class-wp-customize-manager.php
@@ -4702,8 +4702,9 @@ final class WP_Customize_Manager {
 				'previewFrameSensitivity' => 2000,
 			),
 			'theme'                  => array(
-				'stylesheet' => $this->get_stylesheet(),
-				'active'     => $this->is_theme_active(),
+				'stylesheet'  => $this->get_stylesheet(),
+				'active'      => $this->is_theme_active(),
+				'_canInstall' => current_user_can( 'install_themes' ),
 			),
 			'url'                    => array(
 				'preview'       => esc_url_raw( $this->get_preview_url() ),