Ubuntu 4.15 bluetooth source code patched with https://bugzilla.opensuse.org/attachment.cgi?id=770190
Credit goes to Takashi Iwai for the patch
Bluetooth: hci0: don't support firmware rome 0x11020000
Should fix Ubuntu Bug https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1764645
To use
sudo apt install git build-essential dkms
git clone https://github.com/jeremyb31/newbtfix-4.15.git
sudo dkms add ./newbtfix-4.15
sudo dkms install btusb/4.0
Reboot
git clone https://github.com/abnvanand/newbtfix-4.15.git
sudo dkms add ./newbtfix-4.15
sudo dkms install btusb/4.0
reboot
sudo modprobe mt76xx
sudo systemctl enable bluetooth
sudo systemctl start bluetooth
sudo dkms remove btusb/4.0 -k $(uname -r)