* UploadArea should only preventDefault for Escape

This will make accessibility for some things less effortful, since we won't have to define a prior event handler to do whatever should be happening by default.

* Remove workaround for fixed bug in SettingToggle

SettingToggle was toggling itself in response to keydown of space, and then the keyup was doing it again

* Disable embed modal when private status

* Remove `reblogDisabled`

* Make PreviewCard records reuseable between statuses

**Warning!** Migration truncates preview_cards tablec

* Allow a wider thumbnail for link preview, display it in horizontal layout (#4648)

* Delete preview cards files before truncating

* Rename old table instead of truncating it

* Add mastodon:maintenance:remove_deprecated_preview_cards

* Ignore deprecated_preview_cards in schema definition

* Fix null behaviour

* Use system's default font on non web UI pages

* Remove import for Redirect

* Embed modal

* Proxy OEmbed requests from web UI

Commit 9d1f8b9d6a scrolls the columns area
when the route changes since the user is likely to want to see the
rightmost column in such cases.

However, redirection is automatic and does not indicate users' intension.
Do not scroll the columns area due to one.

* Pinned statuses

* yarn manage:translations

Do not reject console.error and console.warn with ESLint rules.

* Add protocol handler. Handle follow intents

* Add share intent

* Improve code in intents controller

* Adjust share form CSS

* feat: Cache status height to avoid expensive renders

* feat: Escape content and emojify in reducers

* fix(css): Remove backface-visibility: hidden from .scrollable

* fix(statuses): Avoid creating DOMParses inside a loop

* Refactored Avatar and AvatarOverlay (DRY) to have 'account' as prop.
Also removed animate attribute from compose navigation bar, which should
have never been there. Added test for avatar overlay.

* fix broken tests

* god dammit another bug in tests! travis please let this pass

* formatting in avatar overlay

The feature to pin column could hide the rightmost column, which is
specified with children property of ColumnsArea.

The user is likely to see the column when the property changed, so scroll
the area in such cases.

* fix(media_modal): Keyboard navigation

* fix(column_back_button): Use native button

* fix(media_gallery): Keyboard navigation

* fix(status_content): Make CW content focusable

* fix(tabs_bar): Check if transition is necessary

* feat(tabs_bar): Only apply optimization for touch devices

* fix(status_action_bar): Use aria-pressed for reblog and favourite button

* fix(column_back_button): Keyboard accessible

* fix(status_content): Make focusable and accessible

* fix(dropdown_menu): Use aria-expanded instead of aria-pressed

* fix(emoji_picker_dropdown): Use aria-expanded instead of aria-hidden

* feat(icon_button): Add aria-expanded

* fix(privacy_dropdown): Use aria-expanded instead of aria-hidden

* Count all URLs in text as 23 characters flat, do not count domain part of usernames

* Add new status text counting logic to web UI

* fix(modal_root): Read type from props, not from component

* fix(status_list): Do not user event.path

* fix(tabs_bar): Allow animation to end before navigating

* fix(tabs_bar): Do not use event.path

* fix(web_push_notification): Do not hard reload tab

* fix(web_push_notification_worker): Guard against null subscription

* refactor: Incorporate pull request feedback

* fix(dropdown_menu): Keyboard navigation

* fix(icon_button): Add aria-pressed attribute

* fix(privacy_dropdown): Make accessible

* fix(emoji_picker_dropdown): Make accessible

* fix(icon_button): Support tabIndex

* fix(actions_modal): Remove icon from tab order

* fix(dropdown_menu): Add role=group

* fix(setting_toggle): Toggle via space key

* fix(dropdown_menu): Remove redundant handling of Space key

* fix(emoji_picker_dropdown): Remove redundant Space key handling

* fix(privacy_dropdown): Remove redundant Space key handling

* fix(status): Switch to article and add aria-posinset, aria-setsize

* fix(status_list): Use role=feed and pass more ARIA props to Status

* chore(eslint): jsx-a11y/role-supports-aria-props

* feat: Web Share for detailed status and account

* fix(account/action_bar): Move share under mention

* fix(compose): Add aria-label for the navigation links

* fix(search): Add input label

* fix(navigation_bar): Link description

* fix(autosuggest_textarea): Add input label

* fix(compose_form): Add input label

* fix(upload_button): Add input label

* fix(account/header): Add link content

* fix(column_header): Use h1 tag

* fix(column_header): Labels move buttons moving column

* fix(settings_text): Add label to input

* fix(column_header): Remove role from h1

* fix(modal_root): Use role=dialog

* fix(modal_root): Focus restauration

* fix(modal_root): Apply inert to sibligs

* fix(column_header): Add role=button

* chore(eslint): Disable jsx-a11y/label-has-for

* fix(dropdown_menu): Open as modal on mobile

* fix(dropdown_menu): Open modal on touch

* fix(dropdown_menu): Show status

* fix(dropdown_menu): Max dimensions and reduce padding

* chore(dropdown_menu): Test new functionality

* refactor: Use DropdownMenuContainer instead of DropdownMenu

* feat(privacy_dropdown): Open as modal on touch devices

* feat(modal_root): Do not load actions-modal async

* fix(column_header): Invalid ARIA role

* fix(column): Remove hidden nodes from the DOM

* refactor(column_link): Remove unused property hideOnMobile

* fix(column_header): Use aria-pressed

* fix(column_header): Make collapsed content not focusable, add focusable property

* fix(column_loading): Make header non-focusable

* fix(column_settings): Use role to group the toggles

* fix(compose): Use nav and remove redundant aria-label

* fix(tabs_tab): Use nav and add aria-label

* fix(app): Add aria-label for settings toggle button

* chore: Run yarn manage:translations

* Improve remote profile disclaimer

* yarn run manage:translations

* feat(compose): More space on mobile devices

* feat(compose): Hide navigation when typing on mobile devices

* fix(compose): Make animation faster

* fix(navigation_bar): Remove hardcoded title

* fix(compose): Prevent accidental bluring

* fix(compose): Increase max-height to 600px

* Add unfollow modal

* unfollowing someone

* remove unnecessary prop

* Exclude self toots from regular expression filter

* refactor