javascript document.cookie missing some pairs

Question

hi all, my script set up like 10 cookies and the browser successfully saved them, but document.cookie only retrieves 9 pairs, the missing pair is as follow:

auth:4ae9Mq1j6tjt7dV6kV6A0piHB6NnNjijBmecax9mA8cfDpSs6pnAcD7H1%2FUqWMIIB%2BbgtKIJ2w1L2GnXkgV2

what happened? is there a character limit in document.cookie? the cookie domain is the same as others.

thanks!