I have an Atmel-ICE-C that I've been using successfully within Ubuntu 18 to program a custom board based on the attiny85 using the terminal and the necessary libraries.
I can use a command like this to program it, for instance:
avrdude -p attiny85 -c atmelice_isp -P usb -U flash:w:[hex_filename].hex:i -U lfuse:w:0xE2:m -U hfuse:w:0xDF:m -U efuse:w:0xff:m
which executes correctly.
Reading up on the internet about debugging (via debugWire), I understood that it's better to set the DWEN bit within the high fuse by using a program like CuteCom, rather than doing it via avrdude using atmelice_dw and setting the hfuse to 0x9F.
Unfortunately, CuteCom doesn't recognize the Atmel-ICE connected to USB (it only detects /dev/ttyACM0, but it spits out "No such device or directory" when I click "open"). I also noticed that the Arduino IDE doesn't detect any USB port either, not even the ttyACM0.
Running lsusb does correctly show the debugger being properly recognized.
Bus 001 Device 005: ID 03eb:2141 Atmel Corp. ICE debugger
I read that it might have to do with udev rules or usergroup settings to be added, but I didn't quite get the steps I should follow.
Any input with regards to that would be highly appreciated :)