Based on Yenthe’s issue on Github https://github.com/wkhtmltopdf/wkhtmltopdf/issues/3898 and thanks to the new builds provided by Ashish Kulkarni, the procedure is straightforward:

sudo wget https://builds.wkhtmltopdf.org/0.12.1.3/wkhtmltox_0.12.1.3-1~bionic_amd64.deb
sudo dpkg -i wkhtmltox_0.12.1.3-1~bionic_amd64.deb
sudo apt-get install -f
sudo ln -s /usr/local/bin/wkhtmltopdf /usr/bin
sudo ln -s /usr/local/bin/wkhtmltoimage /usr/bin

apt-get install -f will install the missing dependencies, which are shown as errors by the dpkg command.

You can find other builds for wkhtmltopdf 0.12.1.3 suitable for Odoo on different Linux systems here: https://builds.wkhtmltopdf.org/0.12.1.3/

Happy Odooing !