The dmesg -T comand does not show any additional problems after above log was created:
[Do Jun 11 23:29:20 2020] usb 2-1: new full-speed USB device number 11 using uhci_hcd
[Do Jun 11 23:29:20 2020] usb 2-1: New USB device found, idVendor=0403, idProduct=6015
[Do Jun 11 23:29:20 2020] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[Do Jun 11 23:29:20 2020] usb 2-1: Product: FT230X Basic UART
[Do Jun 11 23:29:20 2020] usb 2-1: Manufacturer: FTDI
[Do Jun 11 23:29:20 2020] usb 2-1: SerialNumber: D306SGN1
[Do Jun 11 23:29:20 2020] ftdi_sio 2-1:1.0: FTDI USB Serial Device converter detected
[Do Jun 11 23:29:20 2020] usb 2-1: Detected FT-X
[Do Jun 11 23:29:20 2020] usb 2-1: FTDI USB Serial Device converter now attached to ttyUSB0
In my case the indiserver comand shows a rather old version!
2020-06-11T21:38:40: startup: indiserver
Usage: indiserver [options] driver [driver ...]
Purpose: server for local and remote INDI drivers
INDI Library: 1.7.6
Code 1.7.6-tgz. Protocol 1.7.
How can I update to 1.8.6? My version 1.7.6 comes with the Ubuntu stable version installation.