Zhuyin: Are both ㄧㄨㄥ and ㄩㄥ correct renderings of "yong"? I use https://www.yellowbridge.com/chinese/dictionary.php as my primary dictionary. For 用, and any character whose 拼音 would be &quot;yong,&quot; the given 注音 on this site is always ㄧㄨㄥ. However, when inputting characters on a 注音 keyboard, it does not accept ㄧㄨㄥ, but rather ㄩㄥ. Additionally, a Taiwanese friend has told me that there is no such thing as ㄧㄨㄥ.
So is ㄧㄨㄥ just a weird alternate (but still correct) rendering of the sound in 注音? Or is this dictionary site in error, and it actually should always be ㄩㄥ?
Duke University hosts a: Character Conversion Table that may be of good reference for you.

ㄧㄨㄥ = yi + weng
ㄩㄥ = yong

I'd highly recommend not using yellowbridge.