Looks like mIRC is the one doing it wrong
//echo -a $regsubex(a1b,(\d+), this one is fine: \1 - still fine: c\1d - bug??: $chr(3) $chr(3) 07\1)
- the bug doesn't occur because the color sequence is ended
//echo -a $regsubex(a1b,(\d+), this one is fine: \1 - still fine: c\1d - bug??: $chr(3) 07\1)
- the bug shows up, $+ not even requiredscratch that, that was huge non sense!
The markers (\1 here) have to appear literaly in the subtext parameter of $regsubex.