Migrate error from within jQuery when using $.serialize with $.ajaxSettings.traditional

My site uses $.ajaxSettings.traditional = true, and we're working on upgrading to jQuery 3 now. The migrate script is showing a warning when I use $('form').serialize() because the implementation within jQuery uses param without checking the value of the traditional flag.

jQuery.fn.extend( {
	serialize: function() {
		return jQuery.param( this.serializeArray() );
	},
	...
})

(from serialize.js line 99-ish)

I was able to fix the warning by replacing $('form').serialize() with $.param( $('form').serializeArray() , $.ajaxSettings.traditional ), but I'm wondering for future users if it wouldn't be helpful to either:

• Update the migrate documentation to suggest this fix (other programmers might have a hard time understanding what the problem is, since the migrate documentation doesn't reference serialize anywhere; I was confused for a bit before I realized that the offending code was within jQuery), or
• modify the jQuery source to explicitly use the traditional flag in the serialize implementation:

   jQuery.fn.extend( {
   	serialize: function() {
   		return jQuery.param( this.serializeArray(), jQuery.ajaxSettings.traditional );
   	},
   	...
   })
  

Happy to PR if either of those is desirable.

Start with the migration warning in warnings.md and the serialize implementation in src/serialize.js, then compare how $.param handles the traditional flag. Determine whether the accepted resolution is documentation or a jQuery behavior change; done means the chosen path clearly addresses serialize users and is supported by the relevant project checks.