A few code issues

[Dimasmagadan]

https://github.com/ddev-app/feditor/blob/9f7bc988e308f020d4e31c6cf8c6f3175a24fa80/feditor.php#L13
I'd suggest not to use glob and require_once in a loop, cause it can cause several issues:

• Security: The directory contents are not verified, any malicious files can be included and potentially harm the system.
• Performance: require_once is slower compared to other file inclusion methods and reading all files through a loop can slow down the application, especially if the directory has many files. Better to use autoloader or require with a conditional check like if_function_exists() inside
• Maintainability: more files are longer to read and harder to maintain. But could be ok for a small project

https://github.com/ddev-app/feditor/blob/9f7bc988e308f020d4e31c6cf8c6f3175a24fa80/feditor.php#L35
An ob_start inside a WordPress shortcode could lead to a few issues:

• it can cause unexpected behavior: If a shortcode starts an output buffer, any output generated by other plugins or themes that runs before the shortcode's buffer is flushed will be captured and discarded, leading to unexpected behavior.
• Buffering can cause unexpected nesting: If multiple shortcodes start output buffers, the buffers can become nested, causing problems when trying to flush them in the correct order.
• Buffering can cause memory leaks: Output buffering can cause memory leaks if the buffer is not properly flushed, causing the memory usage of the application to increase over time.

https://github.com/ddev-app/feditor/blob/9f7bc988e308f020d4e31c6cf8c6f3175a24fa80/feditor.php#L53
intval() would return 0 for empty value, no need to for an extra empty() check