Upgrade guide: Add jQuery UI 1.14 Upgrade Guide

Also, fix some typos in the 1.12 & 1.13 upgrade guides.

Closes gh-215

page/upgrade-guide/1.12.md

@@ -55,7 +55,7 @@ As of this release we are no longer accepting bug reports for IE8, IE9, or IE10
 
 ### Moved widgets and effects source files into folders
 
-[(#13885)](https://bugs.jqueryui.com/ticket/13885) All widgets, including `mouse.js` (but excluding `widget.js`) were moved to a `widgets` subfolder, so for example, the source for the autocomplete widget is now `ui/widgets/autocomplete.js`. Similarily, all effects (except `effect.js`) were moved to an `effects` subfolder.
+[(#13885)](https://bugs.jqueryui.com/ticket/13885) All widgets, including `mouse.js` (but excluding `widget.js`) were moved to a `widgets` subfolder, so for example, the source for the autocomplete widget is now `ui/widgets/autocomplete.js`. Similarly, all effects (except `effect.js`) were moved to an `effects` subfolder.
 
 ### Explicit CSS dependencies
 

page/upgrade-guide/1.13.md

@@ -10,7 +10,7 @@ This guide will assist in upgrading from jQuery UI 1.12.x to jQuery UI 1.13.x. A
 ## Reminder: API Redesigns
 
 jQuery UI 1.12 introduced API redesigns for Button, Buttonset, Dialog, Draggable, Droppable, Menu, Mouse, Resizable, Selectable, Sortable, Tabs, Tooltip, and Effects. You can read about the API redesign process on the
-[jQuery UI Blog](https://blog.jqueryui.com/2011/03/api-redesigns-the-past-present-and-future/). Although the redesigns introduced breaking changes, **1.12 & 1.13 maintains a lot of compatibility with the 1.11 API by default.** This is accomplished by rebuilding the 1.11 API on top of the 1.12/1.13 API. The default behavior for all 1.12 & 1.13 releases will be to simultaneously use the 1.11 and 1.12/1.13 APIs where possible. If you would like to load just the 1.12/1.13 API without the 1.11 API to prepare for removal of these legacy APIs, you can set the `$.uiBackCompat` flag to `false`.
+[jQuery UI Blog](https://blog.jqueryui.com/2011/03/api-redesigns-the-past-present-and-future/). Although the redesigns introduced breaking changes, **1.12 & 1.13 maintain a lot of compatibility with the 1.11 API by default.** This is accomplished by rebuilding the 1.11 API on top of the 1.12/1.13 API. The default behavior for all 1.12 & 1.13 releases will be to simultaneously use the 1.11 and 1.12/1.13 APIs where possible. If you would like to load just the 1.12/1.13 API without the 1.11 API to prepare for removal of these legacy APIs, you can set the `$.uiBackCompat` flag to `false`.
 
 ```html
 <script src="jquery.js"></script>

page/upgrade-guide/1.14.md

@@ -0,0 +1,75 @@
+<script>{
+	"title": "jQuery UI 1.14 Upgrade Guide",
+	"toc": true
+}</script>
+
+## Overview
+
+This guide will assist in upgrading from jQuery UI 1.13.x to jQuery UI 1.14.x. All changes are listed below, organized by plugin, along with how to upgrade your code to work with jQuery UI 1.14.
+
+## Reminder: API Redesigns
+
+jQuery UI 1.12 introduced API redesigns for Button, Buttonset, Dialog, Draggable, Droppable, Menu, Mouse, Resizable, Selectable, Sortable, Tabs, Tooltip, and Effects. You can read about the API redesign process on the
+[jQuery UI Blog](https://blog.jqueryui.com/2011/03/api-redesigns-the-past-present-and-future/). Although the redesigns introduced breaking changes, **1.12, 1.13 & maintain a lot of compatibility with the 1.11 API by default.** This is accomplished by rebuilding the 1.11 API on top of the 1.12/1.13/1.14 API. However, since 1.14, the default behavior is only loading the new API. If you would like to load the legacy 1.11 API as well, you can set the `$.uiBackCompat` flag to `true`.
+
+```html
+<script src="jquery.js"></script>
+<script>$.uiBackCompat = true;</script>
+<script src="jquery-ui.js"></script>
+```
+
+<p class="note">If you find a regression from the 1.11 API, please report it in the <a href="https://github.com/jquery/jquery-ui/issues/new">bug tracker</a>. Even though the 1.11 API is deprecated, it's important for 1.14 releases not to regress so that users are encouraged to upgrade even if they're not ready to use the new APIs.</p>
+
+## General changes
+
+The main focus of this release was reducing the maintenance. This resulted in a few breaking changes.
+
+### Reduced browser support
+
+Only the latest version of Chrome, Firefox, Safari & Edge are officially supported; there is no support for any version of IE and Edge Legacy. Contrary to what was done in past releases, code supporting unsupported browsers has been deleted.
+
+### Reduced jQuery support
+
+Only the latest jQuery version within each major version of jQuery is supported. To make updates easier, we also run tests with a few other relatively recent versions, but we don't guarantee continued support for them in all jQuery UI releases in the `1.14.x` line. Each jQuery UI version will document on which jQuery versions it was tested - both in the release blog post and in the changelog page at https://jqueryui.com/changelog/.
+
+### The backwards compatibility flag is off by default
+
+Backwards compatibility with the 1.11 API is disabled by default. To re-enable it (restoring the default 1.13 behavior), set the `jQuery.uiBackCompat` flag to true.
+
+### Removed APIs
+
+The following APIs have been removed:
+* `$.fn._form`. Instead of `$( elem )._form()`, use `$( elem ).prop( "form" )`.
+* `$.ui.ie`. No version of IE is supported anymore and this API already only reported IE <11.
+* `$.ui.safeActiveElement`. Use native `document.activeElement`.
+* `$.ui.safeBlur`. Instead of `$.ui.safeBlur( elem )`, use `$( elem ).trigger( "blur" )`.
+
+### Files & directory structure
+
+There have been some minor changes to source files:
+* The deprecated file `ui/core.js` has been removed.
+* Files defining removed APIs have been removed. This includes: `ui/form.js`, `ui/ie.js`, `ui/safe-active-element.js` & `ui.safe-blur.js`.
+* Directories `.github`, `build` & `external` have been removed from the npm package
+
+### Newer jQuery features
+
+As part of making sure jQuery UI doesn't depend on deprecated jQuery APIs, in 1.13 we started using some newer jQuery APIs, polyfilling them in the `jquery-patch.js` file for older jQuery versions. In 1.14, that file is deprecated and it's no longer required for compatibility with some older supported jQuery versions. It is provided for backwards compatibility - so that apps depending on those patches continue to work after the upgrade. The file has no effect in jQuery 3.5.0 or newer.
+
+### Improved tests on PRs
+
+jQuery UI 1.14 is tested in all supported browsers & jQuery versions not only post-merge as was done in the past, but also on every pull request via GitHub Actions.
+
+# Effects
+
+The bundled jQuery Color version has been updated from v2 to v3. This changes the serialized values of color properties to include a space after each comma; e.g. `rgb(127, 127, 127)` instead of `rgb(127,127,127)`. Also, transparent values now report `rgba(0, 0, 0, 0)` instead of `transparent`. This matches the standard browser serialization. It mostly affects direct usage of jQuery Color, for example:
+```js
+// jQuery Color 2.x:
+jQuery.Color( 0, 100, 200    ) + ""; // "rgb(0,100,200)"
+jQuery.Color( 0, 100, 200, 0 ) + ""; // "transparent"
+jQuery.Color( 0,   0,   0, 0 ) + ""; // "transparent"
+
+// jQuery Color 3.x:
+jQuery.Color( 0, 100, 200    ) + ""; // "rgb(0, 100, 200)"
+jQuery.Color( 0, 100, 200, 0 ) + ""; // "rgab(0, 100, 200, 0)"
+jQuery.Color( 0,   0,   0, 0 ) + ""; // "rgab(0, 0, 0, 0)"
+```