Update 2
In ubuntu 18.04, flameshot can be installed directly
sudo apt install flameshot
Update
There is a ppa for this now. Follow the below link
https://launchpad.net/~harish2704/+archive/ubuntu/ppa1
First check whether you have git installed
sudo apt install git
Clone the repository using this command
git clone https://github.com/lupoDharkael/flameshot.git
Go to the clone directory
cd flameshot
Install the dependencies
sudo apt install -y git g++ build-essential qt5-qmake qt5-default qttools5-dev-tools
Compile and install using qmake and make install
qmake
make install #desktop entry fails with warning
To use it
flameshot gui #via terminal
Enjoy smile
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