I am not sure if this is the right place for the documentation of kdesrc-build on https://docs.kde.org/
There is a step missing in the document. On chapter “Setting the Environment to Run Your KDE Plasma™ Desktop” It writes that there is .xsession created by kdesrc-build. That is not the case, because this step of kdesrc-build is not executed at all by following this guide.
Where can I report this, or suggest a change, so that this tutorial will be improved?