[1] [CITE@en-US[UserDataHandler - Web API Interfaces | MDN]]
( ([TIME[2013-11-13 08:25:48 +09:00]] 版))
<https://developer.mozilla.org/en-US/docs/Web/API/UserDataHandler>

[2] [CITE@en[550400 – Fire UserDataHandler for removed nodes]]
( ([TIME[2014-03-09 03:05:08 +09:00]] 版))
<https://bugzilla.mozilla.org/show_bug.cgi?id=550400>