Droidcam unable to find dev/video0

I don't really know what happened with previous droidcam source I was using to install it on 19.10 a few weeks ago. But now I've found a different source which works in my case on 20.04.

Steps I was using which could not be required if you've done them previously. It is better to run the next command:

$ sudo apt install v4l2loopback-utils v4l2loopback-dkms cmake nasm yasm pkg-config libgtk2.0-dev
$ sudo modprobe v4l2loopback
$ v4l2-ctl --list-devices     # check if you have dummy video devices
Dummy video device (0x0000) (platform:v4l2loopback-000):
/dev/video0

Build required dependencies:

cd ~/Downloads
git clone https://github.com/libjpeg-turbo/libjpeg-turbo.git
cd libjpeg-turbo
mkdir build && cd build
cmake -G"Unix Makefiles" ../
make && sudo make install

Build droidcam from sources:

cd ~/Downloads
git clone https://github.com/aramg/droidcam.git
cd droidcam/linux
make
sudo ./install-dkms

Run it:

droidcam &
ffplay /dev/video1    # in your case it could be a different video device

I disabled secure boot - see here https://wiki.ubuntu.com/UEFI/SecureBoot/DKMS

Then reinstalled Droidcam

gcc make linux-headers-`uname -r`

cd /tmp/
wget https://files.dev47apps.net/linux/droidcam_latest.zip
echo "957e5ff9e1762d0e912ee43a5f9083bb droidcam_latest.zip" | md5sum -c --
# OK?
unzip droidcam_latest.zip -d droidcam && cd droidcam
sudo ./install