Unfortunately it is not one of the command line options yet

. The only options we have are below. I could use the --config option, but this means keeping 2 of them in sync apart from the one difference. However i have not seen an easy way to work out where this information is stored or how to work it.
Usage: uex [-h] [-v] [-u] [-r] [-p] [-d] [-c <str>] [-m <str>] [-s <str>] [file to open...]
-h, --help show this help message
-v, --version show version
-u, --uninstall uninstall cleanup
-r, --read-only open files in read-only mode
-p, --print print file
-d, --debug enable debug logging
-c, --config=<str> configuration file to use
-m, --macro=<str> macro to run: [e,][<number of times to execute>,][<macro name>,]<full path to macro file>
-s, --script=<str> script to run: [e,]<script name>
The following standard GTK+ options are also supported:
--class=CLASS Program class as used by the window manager
--name=NAME Program name as used by the window manager
--display=DISPLAY X display to use
--screen=SCREEN X screen to use
--sync Make X calls synchronous
--gtk-module=MODULES Load additional GTK+ modules
--g-fatal-warnings Make all warnings fatal