Use React Router Link in MenuLink

app/soapbox/features/account/components/header.js

@@ -9,6 +9,7 @@ import ImmutablePureComponent from 'react-immutable-pure-component';
 import InlineSVG from 'react-inlinesvg';
 import { defineMessages, injectIntl } from 'react-intl';
 import { connect } from 'react-redux';
+import { Link } from 'react-router-dom';
 
 import { openModal } from 'soapbox/actions/modals';
 import Avatar from 'soapbox/components/avatar';
@@ -612,8 +613,7 @@ class Header extends ImmutablePureComponent {
                           return <MenuDivider key={idx} />;
                         } else {
                           const Comp = menuItem.action ? MenuItem : MenuLink;
-                          // TODO: Add `as: Link` once React Router is upgraded.
-                          const itemProps = menuItem.action ? { onSelect: menuItem.action } : { to: menuItem.to, target: menuItem.newTab ? '_blank' : '_self' };
+                          const itemProps = menuItem.action ? { onSelect: menuItem.action } : { to: menuItem.to, as: Link, target: menuItem.newTab ? '_blank' : '_self' };
 
                           return (
                             <Comp key={idx} {...itemProps} className='group'>

app/soapbox/features/ui/components/profile-dropdown.tsx

@@ -2,6 +2,7 @@ import throttle from 'lodash/throttle';
 import React from 'react';
 import { defineMessages, useIntl } from 'react-intl';
 import { useDispatch } from 'react-redux';
+import { Link } from 'react-router-dom';
 
 import { logOut, switchAccount } from 'soapbox/actions/auth';
 import { fetchOwnAccounts } from 'soapbox/actions/auth';
@@ -115,7 +116,7 @@ const ProfileDropdown: React.FC<IProfileDropdown> = ({ account, children }) => {
             return <MenuDivider key={idx} />;
           } else {
             const Comp: any = menuItem.action ? MenuItem : MenuLink;
-            const itemProps = menuItem.action ? { onSelect: menuItem.action } : { href: menuItem.to };
+            const itemProps = menuItem.action ? { onSelect: menuItem.action } : { to: menuItem.to, as: Link };
 
             return (
               <Comp key={idx} {...itemProps}>