Your plugin throwing the following errors on PHP 7.4
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/Markdown.php:800
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/Markdown.php:1140
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/Markdown.php:1165
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/Markdown.php:1530
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/Markdown.php:1532
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:163
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:165
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 2
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:434
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:443
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 2
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:481
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:500
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:501
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:605
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 2
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:617
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:628
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:629
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:993
Plugin: wp-readme-parser
Deprecated Array and string offset access syntax with curly braces is deprecated 1
wp-content/plugins/wp-readme-parser/includes/Michelf/MarkdownExtra.php:1337
Plugin: wp-readme-parser