How to update your site safely.
Update: See the real usage here.
There are some folders in the
lot folder, whose the contents will not change:
You can change all of the existing files except the contents inside the folders above. Up to whether you want to update the rest of the folders by re-uploading them or by editing each files inside them one by one, or by downloading the static folders I have mentioned above, and then delete the entire site, replace it with the fresh version of Mecha, then put back the downloaded folders to the previous location.