website/layouts/partials/navbar-version-selector.html

{{ $pageDir := index (split (path.Dir .Page.RelPermalink) "/") 1 }}
<!-- special treatment for the homepage. we treat it same as latest docs //-->
{{ if or (eq $pageDir "docs") (eq $pageDir "") }}
	{{ $pageDir = printf "v%s.%s" ( index ( split .Site.Params.latest_release_version "." ) 0 ) ( index ( split .Site.Params.latest_release_version "." ) 1 ) }}
{{ end }}
{{ $pagePath := replace .Page.RelPermalink "docs" "" }}
{{ $pagePath = replace $pagePath $pageDir "" }}

<a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
	{{ $pageDir }} {{ if eq (index .Site.Params.versions 0) $pageDir }} (latest) {{ end }}
</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink" id="navbarVersionSelector">
	{{ range $index, $version := .Site.Params.versions }}
	<a class="dropdown-item" href='/{{ $version }}{{ $pagePath }}' data-docs-version="{{ $version }}">
		{{ $version }} {{ if eq $index 0 }} (latest) {{ end }}
	</a>
	{{ end }}
</div>