Display summary of attachments in description, and mark up content
warning if present, e.g.:

    Attached: 3 images · Content warning: Dota 2

When text is not supposed to be hidden, it looks more like:

    Attached: 3 images

    Here is the text of the toot

With #6817, multilinguagility should be assured...

- Add missing meta description to profiles
- Add canonical rel link to landing page
- Remove linebreaks from title tags
- Add username to profile title
- Add toots/following/followers to profile description tags
- Add next/prev rel links to profiles
- Do not index follower/following variants of profiles

* Fix prev/next links on public profile page

* Don't make pagination urls if no available statuses

* Fix empty check method

* Put left chevron before prev page link

* Add scope for pagination "starting at" a given id

* Status pagination try 2:

s/prev/older and s/next/newer
"older" on left, "newer" on right
Use new scope for "newer" link
Extract magic 20 page size to constant
Remove max_id from feed pagination as it's not respected

* Reinstate max_id for accounts atom stream

* normalize

* Serialize moved accounts into REST and ActivityPub APIs

* Parse federated moved accounts from ActivityPub

* Add note about moved accounts to public profiles

* Add moved account message to web UI

* Fix code style issues

Fix #5597

- Return all images as og:image
- Return videos as og:image (preview) and og:video
- Return profile:username on profiles

* Pinned statuses

* yarn manage:translations

* Redesign public profiles

* Responsive design

* Change public profile status filtering defaults and add options

- No longer displays private/direct toots even if you are permitted access
- By default omits replies
- "With replies" option
- "Media only" option

* Redesign account grid cards

* Fix style issues

* Fix oddities with public profile CSS

* Remove trailing whitespace

* add og:url to stream_item view

* add og:url and text to about/show

* add og:url to profile, followers and follows pages

* Add meta tags for OGP to following & follow page

* simplify render helper

* Follow up #2133

* og:type is only accounts/show

* revert accounts/{following,followers}

* Simplify render in mailer views

* Simplify render in about/more view

* Simplify render in accounts follow views

* Simplify render in recovery code views

* Simplify render in stream entry embed

* Simplify render in stream entries status partial

* Simplify render in authorize follow new view

* Move site title helper to instance helper (name change only)

* Remove newline in <title> tag

* Add site_hostname helper method to wrap up local_domain value

* Use site_hostname helper in places that need local_domain value

* Use local vars in accounts/header partial

* Use local variable in 2fa recovery codes partial

* Add option to disable verify partial doubles

* Add show_landing_strip? helper method

* Use show_landing_strip? helper in accounts and stream entries views

* Fix naming in view specs

An attempt to open a brand new Mastodon instance configured
as SINGLE_USER_MODE=true will cause an exception.

Enable temporary registration if we have no users in the database

Fixes #1817

* Replace will_paginate with kaminari

* Use #page instead of #paginate in controllers

* Replace will_paginate.page_gap with pagination.truncate in i18n

* Customize kaminari views to match prior styles

* Set kaminari options to match prior behavior

* Replace will_paginate with paginate in views

* Add helper method to return Setting.site_title

* Use site_title helper in application layout

* Use site_title value for og:site_name

h-feed, h-card and h-entry

from accounts/tags because it's a terribly inefficient way to paginate
large sets of data