To create a Loot filter, you generally need to use a text editor such as NOTEPAD Some versions of NOTEPAD++ Do work, but most do not from reports. Currently the Encoding must be ANSI or UTF-8
Currently if any part of the file directory contains a non-english character it will not work - this includes your computer username
You can Edit your filter with the game still running. All you need to do is Open it, edit it and save it then press reload in the client.
The basic idea is a list of Show and Hide "blocks" that each specify certain conditions by information provided in each line. Anything matched by a Show block will be shown and anything matched by a Hide block will be hidden. If there are multiple conditions in a block then all of them must be matched for the block to match an item.
Code Breakdown