need help, web player crashed on close the web game

the web player crashed when closed the IE.

“deleting persistent object without writing it first : customassetbundle-f9515…”

i got the logerror in the editor when stop playing in editor,do it has any relationship with the webplayer crash?

There are similar problems but they have been marked in the bug database as fixed. Please can you file a bug report for this (menu: Help > Report A Bug).