There is only one file type that uses the .TEXTEXPANDERSETTINGS extension:
TextExpander Settings File
A TEXTEXPANDERSETTINGS file is a settings file created by TextExpander, a program that allows users to save snippets of often used text and call them by typing shortcuts. It contains all of a user's snippets and is used to transfer snippets from one device to another.
TextExpander saves the snippets of text you type repeatedly, such as an email address, phone number, address, directions, source code, or brand message, and allows you to input the snippets through the typing of shortcuts.
TextExpander saves the snippets in the cloud and updates across all of your synced devices. However, if you do not have sync setup or do not want to set it up, you can transfer the TEXTEXPANDERSETTINGS file by copying it and manually placing it on the other computer. The file's default location on a Mac is in the following location:
You can also transfer the file to an iOS device from your Mac, PC, or iOS device.
NOTE: The TEXTEXPANDERSETTINGS file was introduced in TextExpander 5. The program previously used the .TEXTEXPANDER file in version 4 and earlier.
Settings.textexpandersettings - The default filename of a TEXTEXPANDERSETTINGS file, which stores all of your snippets.
Updated: January 20, 2017