//echo -ag $regex(-sBnx,/^-|\G([snxmd])/Fg) -- first capture group $regml(1)
/F is documented as modifying $regml() results by including empty matches so that it works correctly, but with the above code, it fails and $regml(1) is set to 's' instead of $null.
First match is on '-', which has no capture group, this results in a non participating group being returned by pcre, which mIRC used to ignore without /F, but shouldn't be when /F is used.
