Using .Permalink was causing my site to not compile anymore with version 0.59.1
of Hugo. According to this issue on the Hugo Github repository:
https://github.com/gohugoio/hugo/issues/5868
in menus, .URL is not deprecated and can/should be kept.
At least in Hugo 0.18 (I don't know for prior versions), the variables in the
templates are all set to lowercase even if they are not lowercase in the
config file.
For instance, for a configuration as follows:
[Author]
Handle = "bla"
the variable must be used as .Site.Author.handle and not .Site.Author.Handle.
