Just a little update:
dmesg -w output is:

[ 5021.594797] usb 1-12: new high-speed USB device number 14 using xhci_hcd
[ 5021.743209] usb 1-12: New USB device found, idVendor=2a47, idProduct=201d, bcdDevice=ff.ff
[ 5021.743213] usb 1-12: New USB device strings: Mfr=2, Product=3, SerialNumber=4
[ 5021.743216] usb 1-12: Product: Aquaris_M10_HD
[ 5021.743219] usb 1-12: Manufacturer: Ubuntu
[ 5021.743221] usb 1-12: SerialNumber: FC074240

MTP works fine. I can transfer files no problem.
On my old homeserver running debian buster, adb works (somewhat). I need to try plugging it in a couple of times sometimes. Similar to the installation trouble on the M10.

Thought I'd leave this here for future reference. There is definetly something wrong with the M10 that causes these weird problems though. Thanksfully it has OTG, so I can hook my keyboard up to it.

If a developer wants to maybe try finding out more about the issue, I am up for helping with testing/troubleshooting.

Just a little update:
dmesg -w output is:

[ 5021.594797] usb 1-12: new high-speed USB device number 14 using xhci_hcd
[ 5021.743209] usb 1-12: New USB device found, idVendor=2a47, idProduct=201d, bcdDevice=ff.ff
[ 5021.743213] usb 1-12: New USB device strings: Mfr=2, Product=3, SerialNumber=4
[ 5021.743216] usb 1-12: Product: Aquaris_M10_HD
[ 5021.743219] usb 1-12: Manufacturer: Ubuntu
[ 5021.743221] usb 1-12: SerialNumber: FC074240

MTP works fine. I can transfer files no problem.
On my old homeserver running debian buster, adb works (somewhat). I need to try plugging it in a couple of times sometimes. Similar to the installation trouble on the M10.

Thought I'd leave this here for future reference. There is definetly something wrong with the M10 that causes these weird problems though. Thanksfully it has OTG, so I can hook my keyboard up to it.

If a developer wants to maybe try finding out more about the issue, I am up for helping with testing/troubleshooting.

@Lakotaubp https://forums.ubports.com/topic/1385/bq-m10-hd-adb-does-not-work
After reading this thread, I tried reconnecting it a couple of times and tried different usb controllers.
Interestingly, the tablet only connects to the on-board controllers. Not to one of the two pci-e usb controllers which I have installed (and use regularly).

I am running Linux Mint 19.1 Cinnamon and a M10 HD.

EDIT: As you and some other people on the forums had luck with trying different computers, I got the idea to try to hook the tablet up to my homeserver. And vio la. I got a popup asking if I want to allow usb debugging. The server is an old machine that only has usb 2.0 and runs debian stable.

@Lakotaubp Development mode is on and you can only turn it on when there is a pin set. (When I turn development mode on while the tablet is connected to the computer, I can hear the device disconnected/connected sound)

I don't know how to run this fastboot command. The computer just says:

motofckr9k@MotoFckr9k-Tessa:~$ sudo fastboot oem unlock
< waiting for any device >

That happens while being in the system recovery and while just having the normal system running.
Running the command on the tablet itself does nothing since fastboot is not installed.

UT TweakTool reports that MTP is on. MTP is also working for transfering files.

EDIT: I also tried the remove USB-Troubleshooting privileges option.

@UniSuperBox I have tried that. Being on the apps screen and leaving the screen on.

@UniSuperBox When you say that the device needs to be unlocked: How do I do that?

@Lakotaubp

motofckr9k@MotoFckr9k-Tessa:~$ adb devices
List of devices attached
FC074240	unauthorized

motofckr9k@MotoFckr9k-Tessa:~$ 

I don't get a popup.

Hello

I am trying to follow the anbox installation manual http://docs.ubports.com/en/latest/userguide/dailyuse/anbox.html#how-to-install
But cannot run adb shell:

motofckr9k@MotoFckr9k-Tessa:~$ adb shell
error: device unauthorized.
This adb server's $ADB_VENDOR_KEYS is not set
Try 'adb kill-server' if that seems wrong.
Otherwise check for a confirmation dialog on your device.
motofckr9k@MotoFckr9k-Tessa:~$

I tried:
deleting the adbkey and adbkey.pub on my host computer.
restarting my host computer.
restarting my ubuntu tablet after enabling development mode.

Anyone got any idea how to troubleshoot, or maybe even fix this?

Yeah, in the end I had to remove modemmanager and just try plugging it in a couple of times. (sometimes it works sometimes it doesn't apparently)
Also the tablet didn't boot when the flashing was finished. I had to boot it manually.

I think this picture says all. Thank you very much.

Hello,

I am having a problem installing Ubuntu Touch like shown here: https://docs.ubports.com/en/latest/userguide/install.html#install-on-legacy-android-devices

The flash tool doesn't say anything that I can make sense of and I don't want to remove the M10, in case the tool is actually doing something. Right now it has been stuck for 175 minutes and according to the speed it has shown and the size of the image, it should only take 30 minutes to copy the image to the device.

It would be nice if someone could tell me what step it is stuck at, and if I can safely remove the device to try again.

Here is a paste of the terminal output: https://paste.ubuntu.com/p/rhcqMBktmd/
Also an image of the window: