I can also confirm this issue is present in 1.58.5. We rolled back to 1.58.3 and all is OK again. Not sure what the cause is but here is the stack trace:
2024/02/13 13:12:06 [error] 6498#6498: *2116 FastCGI sent in stderr: "PHP message: PHP Fatal error: Uncaught TypeError: str_contains(): Argument #1 ($haystack) must be of type string, array given in .../wp-includes/blocks.php:1188
Stack trace:
#0 .../wp-includes/blocks.php(1188): str_contains()
#1 .../wp-includes/formatting.php(5226): filter_block_content()
#2 .../wp-includes/class-wp-hook.php(324): wp_pre_kses_block_attributes()
#3 .../wp-includes/plugin.php(205): WP_Hook->apply_filters()
#4 .../wp-includes/kses.php(946): apply_filters()
#5 .../wp-includes/kses.php(754): wp_kses_hook()
#6 .../wp-includes/kses.php(2171): wp_kses()
#7 .../wp-content/plugins/so-widgets-bundle/base/inc/fields/base.class.php(384): wp_kses_post()
#8 .../wp-content/plugins/so-widgets-bundle/base/siteorigin-widget.class.php(759): SiteOrigin_Widget_Field" while reading response header from upstream, client: 70.132.38.37, server: <hidden>, request: "POST /wp-admin/post.php HTTP/1.1", upstream: "fastcgi://unix:/run/php/php8.2-fpm.sock:", host: "<hidden>", referrer: "https://<hidden>/wp-admin/post.php?post=247&action=edit"