CantoDict has the entry 嘩眾取寵 [www.cantonese.sheik.co.uk] , using 嘩 instead of 譁. In fact, CantoDict is currently treating 譁 as a variant of 嘩 for the meaning of “noisy/clamorous”. There is no separate entry for the character 譁.
On the contrary, CUHK site regards 譁 as the standard character for the idiom 譁眾取寵, and 嘩 is the variant.
It is rather unexpected to see that mainland dictionary 廣州話正音字典 recognizes 譁 as the traditional form of 哗 for the “noisy” meaning whereas 漢英對照成語詞典, a HK glossary published in traditional characters, uses 嘩 for the idiom 嘩眾取寵.
On the contrary, CUHK site regards 譁 as the standard character for the idiom 譁眾取寵, and 嘩 is the variant.
It is rather unexpected to see that mainland dictionary 廣州話正音字典 recognizes 譁 as the traditional form of 哗 for the “noisy” meaning whereas 漢英對照成語詞典, a HK glossary published in traditional characters, uses 嘩 for the idiom 嘩眾取寵.