Onboard crashes if I select accented letters

[Josh]

I'm using Linux Manjaro with XFCE, and if I select any accented letter Onboard crashes.
If I start it in the shell I get this error message:

(onboard:53529): Gdk-WARNING **: 03:19:37.289: The program 'onboard' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadValue (integer parameter out of range for operation)'.
  (Details: serial 17272 error_code 2 request_code 135 (XKEYBOARD) minor_code 9)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the GDK_SYNCHRONIZE environment
   variable to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)

[George Thomas (georgefsthomas)]

I'm seeing exactly the same error on attempting to enter the `£` symbol. Also on latest Manjaro XFCE.