Fatal error: Uncaught TypeError: join(): Argument #2 ($array) must be of type ?array, string given in /var/www/vhosts/tummels.ch/tummels/wp-content/plugins/thb-portfolio/inc/frontend.php:258
Stack trace:
#0 /var/www/vhosts/tummels.ch/tummels/wp-content/plugins/thb-portfolio/inc/frontend.php(258): join(Array, ', ')
#1 /var/www/vhosts/tummels.ch/tummels/wp-content/themes/one/templates/thb-portfolio/portfolio-item.php(3): thb_get_portfolio_item_subtitle()
#2 /var/www/vhosts/tummels.ch/tummels/wp-content/themes/one/framework/helpers/helper.frontend.php(326): include('/var/www/vhosts...')
#3 /var/www/vhosts/tummels.ch/tummels/wp-content/plugins/thb-portfolio/inc/frontend.php(34): thb_get_subtemplate('thb-portfolio/', '/var/www/vhosts...', 'portfolio-item....', Array)
#4 /var/www/vhosts/tummels.ch/tummels/wp-content/plugins/thb-portfolio/inc/frontend.php(222): thb_portfolio_get_template_part('portfolio-item', Array)
#5 /var/www/vhosts/tummels.ch/tummels/wp-content/themes/one/templates/thb-portfolio/portfolio.php(39): thb_portfolio_item(Array)
#6 /var/www/vhosts/tummels.ch/tummels/wp-content/themes/one/framework/helpers/helper.frontend.php(326): include('/var/www/vhosts...')
#7 /var/www/vhosts/tummels.ch/tummels/wp-content/plugins/thb-portfolio/inc/frontend.php(34): thb_get_subtemplate('thb-portfolio/', '/var/www/vhosts...', 'portfolio.php', Array)
#8 /var/www/vhosts/tummels.ch/tummels/wp-content/plugins/thb-portfolio/inc/frontend.php(208): thb_portfolio_get_template_part('portfolio', Array)
#9 /var/www/vhosts/tummels.ch/tummels/wp-content/themes/one/template-portfolio.php(58): thb_portfolio_loop()
#10 /var/www/vhosts/tummels.ch/tummels/wp-includes/template-loader.php(106): include('/var/www/vhosts...')
#11 /var/www/vhosts/tummels.ch/tummels/wp-blog-header.php(19): require_once('/var/www/vhosts...')
#12 /var/www/vhosts/tummels.ch/tummels/index.php(17): require('/var/www/vhosts...')
#13 {main}
thrown in /var/www/vhosts/tummels.ch/tummels/wp-content/plugins/thb-portfolio/inc/frontend.php on line 258