Improve the public hashtag page (#9831)

- Fix height not updating when clicking show more on public hashtag page
- Add header to the public hashtag page
- Change text size and margins on the public hashtag page

app/views/tags/_features.html.haml

@@ -1,25 +0,0 @@
-.features-list
-  .features-list__row
-    .text
-      %h6= t 'about.features.real_conversation_title'
-      = t 'about.features.real_conversation_body'
-    .visual
-      = fa_icon 'fw comments'
-  .features-list__row
-    .text
-      %h6= t 'about.features.not_a_product_title'
-      = t 'about.features.not_a_product_body'
-    .visual
-      = fa_icon 'fw users'
-  .features-list__row
-    .text
-      %h6= t 'about.features.within_reach_title'
-      = t 'about.features.within_reach_body'
-    .visual
-      = fa_icon 'fw mobile'
-  .features-list__row
-    .text
-      %h6= t 'about.features.humane_approach_title'
-      = t 'about.features.humane_approach_body'
-    .visual
-      = fa_icon 'fw leaf'

app/views/tags/show.html.haml

@@ -8,5 +8,9 @@
   = javascript_pack_tag 'about', integrity: true, crossorigin: 'anonymous'
   = render 'og'
 
-#mastodon-timeline{ data: { props: Oj.dump(default_props.merge(hashtag: @tag.name)) } }
+.page-header
+  %h1= "##{@tag.name}"
+  %p= t('about.about_hashtag_html', hashtag: @tag.name)
+
+#mastodon-timeline{ data: { props: Oj.dump(default_props.merge(hashtag: @tag.name)) }}
 #modal-container