So do not have to rewrite all the text again, the observation is reported on wowinterface's Legion UI bug forum

http://www.wowinterface.com/forums/showthread.php?t=53939

Essentially

running /dump AuctionCategories[AuctionFrameBrowse.selectedCategoryIndex].subCategories[AuctionFrameBrowse.selectedSubCategoryIndex].subCategories[AuctionFrameBrowse.selectedSubSubCategoryIndex].filters with no categories selected (as in armor, weapons, etc) and not sub or sub sub categories selected throws that blizzard error right away

The error you get trying to run that without anything selected but the browse window frame open is

1x [string "return AuctionCategories[AuctionFrameBrowse..."]:1: attempt to index field '?' (a nil value)
[string "return AuctionCategories[AuctionFrameBrowse..."]:1: in function func' Blizzard_DebugTools\Dump.lua:389: in functionDevTools_DumpCommand'
FrameXML\ChatFrame.lua:2308: in function ?' FrameXML\ChatFrame.lua:4332: in function <FrameXML\ChatFrame.lua:4279> [C]: in functionChatEdit_ParseText'
FrameXML\ChatFrame.lua:4000: in function ChatEdit_SendText' FrameXML\ChatFrame.lua:4036: in functionChatEdit_OnEnterPressed'
[string ":OnEnterPressed"]:1: in function <[string ":OnEnterPressed"]:1>

Locals:
(_temporary) = nil
(_temporary) = nil
(*temporary) = "attempt to index field '?' (a nil value)"