Nope, I have FLRig and FLDigi configured to use my 857 by default.
FLRig is pointed to /dev/serial/by-id/usb-Silicon_Labs_CP2105_Dual_USB_to_UART_Bridge_Controller_00AC0110-if00-port0
Firewolf (/dev/ttyUSB1) is configured to use
/dev/serial/by-id/usb-Silicon_Labs_CP2105_Dual_USB_to_UART_Bridge_Controller_00F8CEC3-if01-port0
No other applications are running using those devices unless I open them
And just for the heck of it I just configured FLDigi to use Hardware PTT (CAT turned off) to /dev/serial/by-id/usb-Silicon_Labs_CP2105_Dual_USB_to_UART_Bridge_Controller_00F8CEC3-if01-port0 with "Use RTS" checked, closed the config window and clicked on "Tune" and it keyed up. Click Tune again (to turn it off) and PTT let go.