Merge branch 'master' into glitch-soc/merge-upstream

Conflicts:
- config/routes.rb
  Upstream changed some admin routes, conflict was because of an added :show
  action for statuses on our side. Kept it.

app/javascript/mastodon/features/getting_started/index.js

@@ -136,7 +136,7 @@ class GettingStarted extends ImmutablePureComponent {
 
           <div className='getting-started__footer'>
             <ul>
-              <li><a href='https://bridge.joinmastodon.org/' target='_blank'><FormattedMessage id='getting_started.find_friends' defaultMessage='Find friends from Twitter' /></a> · </li>
+              <li><a href='/explore' target='_blank'><FormattedMessage id='getting_started.directory' defaultMessage='Profile directory' /></a> · </li>
               {invitesEnabled && <li><a href='/invites' target='_blank'><FormattedMessage id='getting_started.invite' defaultMessage='Invite people' /></a> · </li>}
               {multiColumn && <li><Link to='/keyboard-shortcuts'><FormattedMessage id='navigation_bar.keyboard_shortcuts' defaultMessage='Hotkeys' /></Link> · </li>}
               <li><a href='/auth/edit'><FormattedMessage id='getting_started.security' defaultMessage='Security' /></a> · </li>

app/javascript/mastodon/features/ui/components/embed_modal.js

@@ -77,6 +77,7 @@ class EmbedModal extends ImmutablePureComponent {
             className='embed-modal__iframe'
             frameBorder='0'
             ref={this.setIframeRef}
+            sandbox='allow-same-origin'
             title='preview'
           />
         </div>