Hey! This was requested by a user on mIRC forums.
Load this in a clean mIRC remote and input your twitch channel name where it says INPUT_CHAN_HERE
The checking will start when mIRC starts or in case you don't want to restart you can execute the command /decapi to toggle it on or off. Enjoy!

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alias livestream {
  sockopen -e decapi decapi.me 443
}

alias decapi {
  if ($timer(decapi).secs) { .timerdecapi off | echo -at The Stream Checker is now off }
  elseif (!$timer(decapi).secs) { .timerdecapi 0 200 livestream | echo -at The Stream Checker is now on }
}

alias mytchan { return INPUT_CHAN_HERE }

on *:SOCKOPEN:decapi: {
  sockwrite -nt $sockname GET $+(/twitch/uptime.php?channel=,$mytchan) HTTP/1.1
  sockwrite -nt $sockname Host: decapi.me
  sockwrite $sockname $crlf
}

on *:SOCKREAD:decapi: {
  var %decapi
  sockread %decapi
  while ($sockbr) {
    sockread %decapi
  }
}

on *:sockclose:decapi: {
  var %decapi
  sockread -f %decapi
  if (*not live* iswm %decapi) {
    if (!%streamisoff) {
      set -e %streamisoff 1
      msg $+($chr(35),$mytchan) Stream is now off...
      unset %streamison
    }
  }
  else { 
    if (!%streamison) {
      set -e %streamison 1
      msg $+($chr(35),$mytchan) Stream is now on!
      unset %streamisoff
    }
  }
}

ON *:START: { .timerdecapi 0 200 livestream }

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