Throw an exception if the addChildren() method of HtmlTag receives something that is not an HtmlConvertible
Summary
HtmlTag children must be HtmlConvertible instances: we should enforce this behaviour by throwing an exception if the client passes something different.
Current Behavior
PHP throws a generic error if something that is not an HtmlConvertible is passed, since the display
method of Page is attempting to convert an object to string.
Desired Behavior
The HtmlTag instance should immediately stop the client with a useful message.
Migration Plan
This improvement doesn't affect pre-existing applications.
Edited by username-removed-602692