As this GitHub - wkhtmltopdf/wkhtmltopdf: Convert HTML to PDF using Webkit (QtWebKit) repo is archived, there will be no more updates from the owner and this tool is highly used in ERPNext 14.
Is there any alternative solution or approach there or it will continue use in ERPNext 14 and onwards new versions?
You can actually build the package yourself. the packaging repo is still active and the packages are still actively maintained.
You can go to the packaging repo and download it and it is still actively maintained. Just follow the steps below to install any release you need:
wget https://github.com/wkhtmltopdf/packaging/releases/download/0.12.6.1-2/wkhtmltox_0.12.6.1-2.jammy_amd64.deb && \
sudo dpkg -i wkhtmltox_0.12.6.1-2.jammy_amd64.deb && \
sudo cp /usr/local/bin/wkhtmlto* /usr/bin/ && \
sudo chmod a+x /usr/bin/wk*
sudo rm wk*
You can copy the entire command and paste it and it will install the version for ubuntu 22.04 or you can visit the repo and copy the download link to the package version for your OS version if you need other versions.
Hope this helps.