original.js

var mapp = {
	a: "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ?!".split(""),
	b: "a͠ þ̌ ç̌ d̑͢ ȇ͝ f͛ͪ g͖͉ͫͥͨ h҉ î̩́ jͫ͏̙̤ kͫ͏ l̂ mͧ̾ͬ n ̔̉o p​̅ͫ͏̙̤ q​̅ͫ͏ r͎̩̱͔ s҉ † µ v͚̖͔͚̖͔͚̖͔ w͚̖͔ ×ͧ̾ͬ ¥ͧ̾ͬ z̈́̂̈́ A̡͊͠͝ B̀ Cͭ̏ͥͮ͟ Ð Eͧ̾ͬ͛ͪ̈́ F̷̭̯̙̲̝͖ G҉ H̸̡̪̯ͨ͊̽̅̾̎ | J̩́ K͠ L͑ M͊̒ N̐ Θ ͠P̯͍̭ Q​̅ͫ͏̙̤ R̘̝̙ͤ͂̾̆  $̝ͤ͂̾̆ T̈́̂̈́ U̲̖̚͜ V̈́̂̈́ W̷̙̲ X̚͜ Y̷̙ Z͍̭҉ ‽ ‽".split(" ")
};
$(".message .content").each(function() {
	var text = $(this).text(),
	chars = text.split(''),
	output = "";
	chars.forEach(function(char) {
		var p = mapp.a.indexOf(char);
		if( p !== -1 ) {
			output += mapp.b[p];
		} else {
			output += char;
		}
	});
	$(this).text(output);
});

Unicode Bookmarklet.js

javascript:var mapp={a:"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ?!".split(""),b:"a\u0360 \u00fe\u030c \u00e7\u030c d\u0311\u0362 e\u0311\u035d f\u035b\u036a g\u036b\u0365\u0368\u0356\u0349 h\u0489 i\u0302\u0341\u0329 j\u036b\u034f\u0319\u0324 k\u036b\u034f l\u0302 m\u0367\u033e\u036c n \u0314\u0309o p\u200b\u0305\u036b\u034f\u0319\u0324 q\u200b\u0305\u036b\u034f r\u034e\u0329\u0331\u0354 s\u0489 \u2020 \u00b5 v\u035a\u0316\u0354\u035a\u0316\u0354\u035a\u0316\u0354 w\u035a\u0316\u0354 \u00d7\u0367\u033e\u036c \u00a5\u0367\u033e\u036c z\u0344\u0302\u0344 A\u0360\u0321\u034a\u035d B\u0340 C\u036d\u030f\u0365\u036e\u035f \u00d0 E\u0367\u033e\u036c\u035b\u036a\u0344 F\u032d\u032f\u0337\u0319\u0332\u031d\u0356 G\u0489 H\u0368\u034a\u033d\u0305\u033e\u030e\u0321\u0338\u032a\u032f | J\u0341\u0329 K\u0360 L\u0351 M\u034a\u0312 N\u0310 \u0398 \u0360P\u032f\u034d\u032d Q\u200b\u0305\u036b\u034f\u0319\u0324 R\u0364\u0342\u033e\u0306\u0318\u031d\u0319  $\u0364\u0342\u033e\u0306\u031d T\u0344\u0302\u0344 U\u031a\u035c\u0332\u0316 V\u0344\u0302\u0344 W\u0337\u0319\u0332 X\u031a\u035c Y\u0337\u0319 Z\u034d\u032d\u0489 \u230d \u230d".split(" ")};$(".message .content").each(function(){var a="";$(this).text().split("").forEach(function(b){var c=mapp.a.indexOf(b);a=-1!==c?a+mapp.b[c]:a+b});$(this).text(a)});;

Any word please, how this can be used from my browser??
Thanks!