Merge branch 'canary' into master (#711)

* refactor(i18n): simplify the structure of the translation file

* chore: prepare repository for v4.0.0-alpha

* chore: modify go.mod to v4

* refactor: migrate theme configuration to TOML

* fix: exampleSite not using correct theme

* feat: add favicon from assets folder

* refactor: drop linear grandient background feature

remove node-vibrant from dependencies

* feat: use Hugo's code block render hook to implement code copy button

Now it can have i18n support

* refactor: delete color.ts

* refactor: delete Emoji support post from example site

* refactor: drop support for `hidden` field in front matter

* feat: upgrade to PhotoSwipe v5

* chore: bump the required hugo version to 0.100.0

* refactor: remove PhotoSwipe from external.yaml

* fix: extra margin in search result

* fix: incorrect markdown heading level in example site

* refactor: remove some usages of `default` in template

No longer needed thanks to Hugo's configuration merge

* fix: one line codeblock style in firefox

closes https://github.com/CaiJimmy/hugo-theme-stack/issues/564

* feat: add style to new codeblock

* feat: i18n support for codeblock copy text

* fix(menu): jitter when closing menu

It's caused by flexbox gap property, which can't animate

* fix(search): long text overflows under the Search icon

closes https://github.com/CaiJimmy/hugo-theme-stack/issues/515

layouts/partials/head/colorScheme.html

@@ -1,5 +1,5 @@
-{{- $defaultColorScheme := default "auto" .Site.Params.colorScheme.default -}}
-{{- if not (default false .Site.Params.colorScheme.toggle) -}}
+{{- $defaultColorScheme := .Site.Params.colorScheme.default -}}
+{{- if not .Site.Params.colorScheme.toggle -}}
     {{/* If toggle is disabled, force default scheme */}}
     <script>
         (function() {

layouts/partials/head/head.html

@@ -19,7 +19,12 @@
 {{- end -}}
 
 {{ with .Site.Params.favicon }}
-    <link rel="shortcut icon" href="{{ . }}" />
+    {{ $favicon := resources.Get . }}
+    {{ if $favicon }}
+        <link rel="shortcut icon" href="{{ $favicon.RelPermalink }}" />
+    {{ else }}
+        {{ errorf "Failed loading favicon from %q" . }}
+    {{ end }}
 {{ end }}
 
 {{- template "_internal/google_analytics.html" . -}}

layouts/partials/head/opengraph/provider/twitter.html

@@ -11,6 +11,6 @@
 
 {{- $image := partialCached "helper/image" (dict "Context" . "Type" "opengraph") .RelPermalink "opengraph" -}}
 {{- if $image.exists -}}
-    <meta name="twitter:card" content="{{ default `summary_large_image` .Site.Params.opengraph.twitter.card }}">
+    <meta name="twitter:card" content="{{ .Site.Params.opengraph.twitter.card }}">
     <meta name="twitter:image" content='{{ absURL $image.permalink }}' />
 {{- end -}}