PHP Fatal error: Array and string offset access syntax with curly braces is no longer supported

[maxpostal]

Hello!

Describe the bug
When I press the GO button in order to check my theme I get the error:

PHP Fatal error: Array and string offset access syntax with curly braces is no longer supported in /opt/lampp/htdocs/my.site/wp-content/plugins/theme-sniffer/vendor/squizlabs/php_codesniffer/src/Config.php on line 420

To Reproduce
Steps to reproduce the behavior:

1. Go to '/wp-admin/admin.php?page=theme-sniffer'
2. Chose any theme, for example, 'Twenty Twenty' one.
3. Click on 'GO'.
4. Wait a while.
5. See the error in debug.log (define( 'WP_DEBUG', true ); required in wp-config.php).

Expected behavior
Result of the theme check.

Screenshots
No required.

Environment (please complete the following information):

• OS: Linux
• Browser: Chrome
• Version: 87.0.4280.88 (Official Build) (64-bit)
• PHP Version: 8.0.0
• WP Version 5.6

Additional context
Local web server XAMPP.

[stefanofattori]

After 3 years nobody has a solution? I still have this problem...

[carolinan]

This project is not maintained.

[stefanofattori]

WordPress.org theme review told me to download it to check my developed theme before upload it on wordpress directory.... it also mentioned on wordpress guidlines...