After to updating WordPress to WP 5.8, you might have received this Low Severity Problem security warning message from WordFence plugin which says “Old WordPress core file not removed during update”.
Files with a problem
The problem here is that after updating to WordPress 5.8, some old WP Core files below are not removed as it should be.
How to fix the error
Using Cpanel File Manager or FTP
- Go to publi_html
- Then wp-includes
- Select CSS folder
- Select dist folder
- Select editor folder
- Delete the following files (editor-styles-rtl.css, editor-styles-rtl.min.css, editor-styles.css, and editor-styles.min.css).
- Go back to Wordfence and start new scan. The issues should have been resolved.
Deleting those four files will not cause any problem in your website as they are not supposed to be included in 5.8+ versions of WordPress Core files.
Alternatively, you can leave the files there and wait for the next WordPress update to be released. It is likely to solve the issue as it has been reported as a known wp core bug.