* Add responsive panels to the single-column layout

* Fixes

* Fix not being able to save the preference

* Fix code style issues

* Set max-height on the compose textarea and add a link to relationship manager

- Add potential side panels to single column layout
- Hide FAB on large screens

* Move TabsBar rendering logic from CSS to the ColumnsArea component

* Add forceSingleColumn mode

* Add unread notifications counter to tabs bar

* Add toggle to control `forceSingleColumn`

* Increase paddings in mobile layout responsively at large sizes

[#3815]

Display the boost modal also when unboosting toots.

* Add "view context" button to media modal when opened from gallery

* Add "view context" button to video modal

Allow closing the video modal by navigating back in the browser,
just like the media modal

* Add blurhash

* Use fallback color for spoiler when blurhash missing

* Federate the blurhash and accept it as long as it's at most 5x5

* Display unknown media attachments as blurhash placeholders

* Improve style of embed actions and spoiler button

* Change blurhash resolution from 3x3 to 4x4

* Improve dependency definitions

* Fix code style issues

* Do not crash the whole UI when loading an invalid column

* Add error boundary component to catch Web UI crashes

* Add stack trace on supported browsers

* Add component stack info, pre-format everything for github

* Make “Reload” a clickable link that calls window.location.reload()

* Remove elephant friend from error boundary, make title stand out more

* Simplify error boundary to only a graphic

* Refactor uses of icons to an Icon component in web UI

* Refactor options passed to the Icon component

* Make tests work with absolute component paths

* Prepare to load onboarding as a full page

* Update the first-time introduction

* Improve responsive design

* Replace speech bubble with logo

* Increase text size and reword first paragraph

* Add add user to list from thier profile

* Fix listAdderCss

* Change documentation URL

* Fix hardcoded documentation URL in locales

* Revert "Fix some icon names changed by the Font Awesome 5. (#8796)"

This reverts commit 3f9ec3de82.

* Revert "Migrate to font-awesome 5.0. (#8799)"

This reverts commit 8bae14591b.

* Revert "Fix some icons names, unavailable in fontawesome5 (free license). (#8792)"

This reverts commit b9c727a945.

* Revert "Update the icon name changed by the Font Awesome 5. (#8776)"

This reverts commit 17af4d27da.

* Revert "Add bot icon to bot avatars and migrate to newer version of Font Awesome (#8484)"

This reverts commit 4b794e134d.

- pencil => pencil-alt
- sliders => sliders-h

related: #8484 #8776

This includes clicks on hashtags, mentions, display names and media in the
timeline; and usernames in reply-indicator, detailed status, and the boost
modal.

* Compensate for scrollbar disappearing when media modal visible

Make auth pages backgrounds lighter

* Fix typo

* Also display replies in report modal

* Allow report modal to be up to 80% of viewport height

* Use narrow no-break space where needed in the French translation

* Add variables for text colors

* Change variables in sass files

* Apply text color variables for recently added colors

* Fix text colors of emoji mart anchors

* Fix text colors of search__input

* Fix text colors of text area of compose-form

* Fix icon colors of privacy dropdown and modal

* Inverted icon colors by classname

* Change variables in boost.scss

* Change action-button-color

* Fix text colors of pre-header

* Added a timeline for Direct statuses
* Lists all Direct statuses you've sent and received
* Displayed in Getting Started
* Streaming server support for direct TL

* Changes to match other timelines in 2.0

* Add search item to tab bar for mobile devices

* Fix missing prop validation

Unfortunately the new hammer.js functionality wasn't correctly tested and didn't work across devices and browsers, as such, it's best to revert PR #6944 until we can revisit this functionality and make it work across all devices and browsers that are supported by Mastodon.

This reverts commit 5021c4e9ca.

* Add eslint-plugin-promise to detect uncaught rejections

* Move alert generation for errors to actions/alert

* Add missing rejection handling for Promises

* Use catch() instead of onReject on then()

Then it will catches rejection from onFulfilled. This detection can be
disabled by `allowThen` option, though.

add <div.zoomable-image__margin/> to keep margin of the image on zooming
move setting `scrollLeft` and `scrollTop` of container from callback of
`setState` to `componentDidUpdate`
add 'hammerjs' package for touch gesture detection
rewrite `ZoomableImage` using 'hammerjs'

avoid using JS to set height of ReactSwipeableViews component
reduce max-height of <img/> to 80% to avoid the screen covered by image

* Use object-position with object-fit instead of JS top/left

* Fix focal point modal

TabsBar refers to router, which is a private context property of
react-router. withRouter is a recommended alternative. It also allows to
track location changes even if React.PureComponent is used.