[TrustedOrb]

Set up WordPress on my Windows PC. When I click on “Forums”, I get the error
Fatal error: Uncaught Error: [] operator not supported for strings in C:\xampp\htdocs\wordpress\wp-content\plugins\bbpress\includes\forums\functions.php:1800 Stack trace: #0 C:\xampp\htdocs\wordpress\wp-includes\class-wp-hook.php(298): bbp_pre_get_posts_normalize_forum_visibility(Object(WP_Query)) #1 C:\xampp\htdocs\wordpress\wp-includes\class-wp-hook.php(323): WP_Hook->apply_filters('', Array) #2 C:\xampp\htdocs\wordpress\wp-includes\plugin.php(515): WP_Hook->do_action(Array) #3 C:\xampp\htdocs\wordpress\wp-includes\class-wp-query.php(1683): do_action_ref_array('pre_get_posts', Array) #4 C:\xampp\htdocs\wordpress\wp-includes\class-wp-query.php(3248): WP_Query->get_posts() #5 C:\xampp\htdocs\wordpress\wp-includes\class-wp.php(617): WP_Query->query(Array) #6 C:\xampp\htdocs\wordpress\wp-includes\class-wp.php(735): WP->query_posts() #7 C:\xampp\htdocs\wordpress\wp-includes\functions.php(955): WP->main(Array) #8 C:\xampp\htdocs\wordpress\wp-admin\includes\post.php(1072): wp(Array) #9 C:\xampp\htdocs\wordpress\wp-admin\includ in C:\xampp\htdocs\wordpress\wp-content\plugins\bbpress\includes\forums\functions.php on line 1800
New forums can be created without any errors, but when I click on the URL of the new forum, I get the same error again.

[TrustedOrb]

Sorry, the problem is solved after installing bbPress 2.6 beta 2 from https://bbpress.org/download/. I was on bbPress 2.5.13, WordPress 4.8, PHP 7.x