[TxMt] Where does TM store "Treat Files with Extension..."

Hi All,

In the project drawer, a right-click on a file icon opens a dialog where one can find : Treat Files with ".xxx" Extension as Text Where does TM store this infos afterwards? Did not find anything in "Application Support" nor in "Preferences"

The point is to have TM consider files with a variable extension as text, like the ones I have to deal with : the extension is a 8-digit number representing the date the document was edited (*.20041023 for instance)

Can we use regular expression for this (like \d{8})?

Found nothing in the Wiki nor in Help.

Thanks,