Highlight active tab in action bar (#8673)

* NavLinks with activeclass instead of Link in actionbar to highlight active tab

* highlight border-bottom in action bar consistent to public view

app/javascript/mastodon/features/account/components/action_bar.js

@@ -2,7 +2,7 @@ import React from 'react';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import PropTypes from 'prop-types';
 import DropdownMenuContainer from '../../../containers/dropdown_menu_container';
-import { Link } from 'react-router-dom';
+import { NavLink } from 'react-router-dom';
 import { defineMessages, injectIntl, FormattedMessage } from 'react-intl';
 import { me } from '../../../initial_state';
 import { shortNumberFormat } from '../../../utils/numbers';
@@ -147,20 +147,20 @@ export default class ActionBar extends React.PureComponent {
 
         <div className='account__action-bar'>
           <div className='account__action-bar-links'>
-            <Link className='account__action-bar__tab' to={`/accounts/${account.get('id')}`} title={intl.formatNumber(account.get('statuses_count'))}>
+            <NavLink exact activeClassName='active' className='account__action-bar__tab' to={`/accounts/${account.get('id')}`} title={intl.formatNumber(account.get('statuses_count'))}>
               <FormattedMessage id='account.posts' defaultMessage='Toots' />
               <strong>{shortNumberFormat(account.get('statuses_count'))}</strong>
-            </Link>
+            </NavLink>
 
-            <Link className='account__action-bar__tab' to={`/accounts/${account.get('id')}/following`} title={intl.formatNumber(account.get('following_count'))}>
+            <NavLink exact activeClassName='active' className='account__action-bar__tab' to={`/accounts/${account.get('id')}/following`} title={intl.formatNumber(account.get('following_count'))}>
               <FormattedMessage id='account.follows' defaultMessage='Follows' />
               <strong>{shortNumberFormat(account.get('following_count'))}</strong>
-            </Link>
+            </NavLink>
 
-            <Link className='account__action-bar__tab' to={`/accounts/${account.get('id')}/followers`} title={intl.formatNumber(account.get('followers_count'))}>
+            <NavLink exact activeClassName='active' className='account__action-bar__tab' to={`/accounts/${account.get('id')}/followers`} title={intl.formatNumber(account.get('followers_count'))}>
               <FormattedMessage id='account.followers' defaultMessage='Followers' />
               <strong>{shortNumberFormat(account.get('followers_count'))}</strong>
-            </Link>
+            </NavLink>
           </div>
 
           <div className='account__action-bar-dropdown'>

app/javascript/styles/mastodon/components.scss

@@ -1297,6 +1297,11 @@ a .account__avatar {
   flex: 0 1 100%;
   border-right: 1px solid lighten($ui-base-color, 8%);
   padding: 10px 0;
+  border-bottom: 4px solid transparent;
+
+  &.active {
+    border-bottom: 4px solid $ui-highlight-color;
+  }
 
   & > span {
     display: block;