Switching from Text to Visual editing replaces HTML character entities w/ ascii

Hello! ~~ Attempting to hide email addresses from SPAM bots, I convert ascii addresses to decimal “character entities” i.e. A = A. This has been working very well. However, I notice when shifting from “Text” editing mode to “Visual” editing mode WP returns decimal “character entities” back to ascii!

Searching for a fix, I have added the following suggestion to functions.php:

 function override_mce_options($initArray) {
	$opts = '*[*]';
	$initArray['valid_elements'] = $opts;
	$initArray['extended_valid_elements'] = $opts;
	return $initArray;
}
add_filter('tiny_mce_before_init', 'override_mce_options');

without success.

Can you recommend a way to prevent WP from replacing decimal “character entities” back to ascii when shifting from “Text” editing mode to “Visual” editing mode?

Thank You for Your Attention! ~~ Jacob

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