Strange coding showing on each page

WordPress version: 5.1 running Avada Child theme.
Strong Testimonials version 2.36
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Since the most recent upgrade, another problem (linked to Strong Testimonials, I think) is that each page on my website now displays four long warnings and MASSES of white space making pages look blank.

The warnings are:

Warning: Declaration of Post_Types_Order_Walker::start_lvl(&$output, $depth) should be compatible with Walker::start_lvl(&$output, $depth = 0, $args = Array) in /home/oakleyit/public_html/wp-content/themes/Avada/framework/plugins/post-types-order/post-types-order.php on line 0

Warning: Declaration of Post_Types_Order_Walker::end_lvl(&$output, $depth) should be compatible with Walker::end_lvl(&$output, $depth = 0, $args = Array) in /home/oakleyit/public_html/wp-content/themes/Avada/framework/plugins/post-types-order/post-types-order.php on line 0

Warning: Declaration of Post_Types_Order_Walker::start_el(&$output, $page, $depth, $args) should be compatible with Walker::start_el(&$output, $object, $depth = 0, $args = Array, $current_object_id = 0) in /home/oakleyit/public_html/wp-content/themes/Avada/framework/plugins/post-types-order/post-types-order.php on line 0

Warning: Declaration of Post_Types_Order_Walker::end_el(&$output, $page, $depth) should be compatible with Walker::end_el(&$output, $object, $depth = 0, $args = Array) in /home/oakleyit/public_html/wp-content/themes/Avada/framework/plugins/post-types-order/post-types-order.php on line 0

Does anyone know what is causing this and what I should do?

PS – I’m no developer and so websites (in particular WordPress) are strange to me so please be gentle with your guidance :/

Thanks

• This topic was modified 6 years ago by Jan Dembowski. Reason: Fixed formatting

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