Array to String conversion and undefined array key

2021/07/07 13:56:16 [error] 45809#45809: *3404 FastCGI sent in stderr: "PHP message: PHP Warning:  Array to string conversion in /var/www/www.wyvern-va.uk/wp-includes/formatting.php on line 1098" while reading upstream, client: 82.9.100.224, server: dev.wyvern-va.uk, request: "GET /wp-admin/customize.php?return=%2Fwp-admin%2F HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php8.0-fpm.sock:", host: "dev.wyvern-va.uk", referrer: "https://dev.wyvern-va.uk/wp-admin/"
2021/07/07 13:56:16 [error] 45809#45809: *3404 FastCGI sent in stderr: "PHP message: PHP Warning:  Array to string conversion in /var/www/www.wyvern-va.uk/wp-includes/formatting.php on line 1098

PHP message: PHP Warning:  Array to string conversion in /var/www/www.wyvern-va.uk/wp-includes/formatting.php on line 1098" while reading upstream, client: 82.9.100.224, server: dev.wyvern-va.uk, request: "GET /wp-admin/customize.php?return=%2Fwp-admin%2F HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php8.0-fpm.sock:", host: "dev.wyvern-va.uk", referrer: "https://dev.wyvern-va.uk/wp-admin/"

2021/07/07 13:46:05 [error] 45810#45810: *3303 FastCGI sent in stderr: "PHP message: PHP Warning:  Undefined array key "disable_all" in /var/www/www.wyvern-va.uk/wp-content/plugins/scroll-triggered-animations/frontend/init.php on line 2" while reading response header from upstream, client: 82.9.100.224, server: dev.wyvern-va.uk, request: "GET /wp-admin/plugins.php?plugin_status=all&paged=1&s HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php8.0-fpm.sock:", host: "dev.wyvern-va.uk", referrer: "https://dev.wyvern-va.uk/wp-admin/customize.php?return=%2Fwp-admin%2Fplugins.php%3Fplugin_status%3Dall%26paged%3D1%26s"

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