Hi,
I noticed that the UTF-8 encoding looks a little iffy on mIRC. Everyone using mIRC has the same issue as far as I know and can see, so it shouldn't be on my end. Also, some people are saying that they can't see what I'm typing, so I started looking into it.
mIRC encodes non-ascii characters in double encoded UTF-8, while it should use plain UTF-8. It has no issues decoding regular UTF-8 or the messed up double encoded UTF-8.
Example
mIRC encodes the character รค (U+00E4, LATIN SMALL LETTER A WITH DIAERESIS) as C3 83 C2 A4
In plain UTF-8, it should be C3 A4