What are some common pitfalls when transitioning from PHP 5.6 to PHP 7.4?

Issue: One common pitfall when transitioning from PHP 5.6 to PHP 7.4 is the removal of deprecated features and changes in syntax. This can cause compatibility issues with existing code that relies on deprecated functions or syntax. Solution: To address this issue, it is important to update the codebase to use the latest PHP syntax and replace deprecated functions with their modern equivalents. Additionally, it is recommended to thoroughly test the application after making these changes to ensure its functionality is not affected.

// Example code snippet showing how to update deprecated functions in PHP 7.4

// Deprecated function in PHP 5.6
$oldArray = array('foo', 'bar', 'baz');

// Updated code for PHP 7.4
$newArray = ['foo', 'bar', 'baz'];