Activating plugin leads to fatal error

Wordpress Ver : 5.6

PHP Ver : 7.3

Error I am getting is as under :

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Warning: Illegal string offset ‘display’ in /usr/local/lsws/stroke/html/wp-content/plugins/bbpress-post-topics/index.php on line 924

Fatal error: Uncaught Error: Cannot unset string offsets in /usr/local/lsws/stroke/html/wp-content/plugins/bbpress-post-topics/index.php:926 Stack trace: #0 /usr/local/lsws/stroke/html/wp-includes/class-wp-hook.php(287): bbppt_activate(”) #1 /usr/local/lsws/stroke/html/wp-includes/class-wp-hook.php(311):

WP_Hook->apply_filters(”, Array) #2 /usr/local/lsws/stroke/html/wp-includes/plugin.php(484): WP_Hook->do_action(Array) #3 /usr/local/lsws/stroke/html/wp-admin/plugins.php(193): do_action(‘activate_bbpres…’) #4 {main} thrown in /usr/local/lsws/stroke/html/wp-content/plugins/bbpress-post-topics/index.php on line 926
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Please advise resolution

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