Index: src/wp-admin/includes/class-wp-plugins-list-table.php
===================================================================
--- src/wp-admin/includes/class-wp-plugins-list-table.php	(revision 33084)
+++ src/wp-admin/includes/class-wp-plugins-list-table.php	(working copy)
@@ -620,7 +620,7 @@
 					// Details link using API info, if available
 					if ( isset( $plugin_data['slug'] ) && current_user_can( 'install_plugins' ) ) {
 						$plugin_meta[] = sprintf( '<a href="%s" class="thickbox" aria-label="%s" data-title="%s">%s</a>',
-							esc_url( network_admin_url( 'plugin-install.php?tab=plugin-information&plugin=' . $plugin_data['slug'] .
+							esc_url( admin_url( 'plugin-install.php?tab=plugin-information&plugin=' . $plugin_data['slug'] .
 								'&TB_iframe=true&width=600&height=550' ) ),
 							esc_attr( sprintf( __( 'More information about %s' ), $plugin_name ) ),
 							esc_attr( $plugin_name ),
Index: src/wp-admin/plugin-install.php
===================================================================
--- src/wp-admin/plugin-install.php	(revision 33084)
+++ src/wp-admin/plugin-install.php	(working copy)
@@ -17,7 +17,7 @@
 if ( ! current_user_can('install_plugins') )
 	wp_die(__('You do not have sufficient permissions to install plugins on this site.'));
 
-if ( is_multisite() && ! is_network_admin() ) {
+if ( is_multisite() && ! is_network_admin() && ( defined( 'IFRAME_REQUEST' ) && ! IFRAME_REQUEST ) ) {
 	wp_redirect( network_admin_url( 'plugin-install.php' ) );
 	exit();
 }