Go back to the original device/app_defaults.php. What I had in mind for this was a restore default button. When the administrator decides they want to update it. They may not want or need additional vendors.
Added the rest of the aastra function key options to app_config. And to
my surprise the functions would not save to the database, found the
problem to be the app_defaults logic would only allow adding on a fresh
install. So I fixed it to work with a update also.
Cause all the .php files containing lines ending with \r\n to instead end with \n.
DYI with:
find fusionpbx -type f -name '*.php' -exec dos2unix '{}' \;