## Removed Function Callbacks

Three function callbacks have been removed in favor of using events. 

- `onChange`
- `onInput`
- `onSearch`

While this is a breaking change, the change in your application should be as simple as swapping the
prop you were using for an event.

### `onChange` & `onInput`

In v2.x, Overwriting `onChange` in an application was more likely to break vue-select's internals 
and cause issues. The `input` event provides identical functionality and can be swapped out in your 
application. 

```html
<!-- version 2: -->
<v-select :on-change="doSomething" />

<!-- version 3: -->
<v-select @input="doSomething" />
```

Additionally, the `change` event has been removed. This event was redundant, `input` should be used 
instead.

```html
<!-- version 2: -->
<v-select @change="doSomething" />

<!-- version 3: -->
<v-select @input="doSomething" />
```

### `onSearch`

The `onSearch` prop was removed for the same reason as `onChange` and `onInput`. The `search` event
has always provided the same parameters and can be used in it's place.

```html
<!-- version 2: -->
<v-select :on-search="doSomeAjax" />

<!-- version 3: -->
<v-select @search="doSomeAjax" />
```

## Separated CSS

CSS was removed from the JS bundle in favor of a separate CSS file to support SSR and easier
customization.

  ```js
  @import vSelect from 'vue-select`;
  @import 'vue-select/dist/vue-select.css';
  ```

## New Class Selector Prefix

In order to avoid CSS collisions and allow for low specificity overrides of CSS, all classes have 
been renamed to include the `vs__` prefix. The full list of renamed classes are listed below:

| original | renamed |
| ------- | --------- |
| `.open-indicator` | `.vs__open-indicator` |
| `.dropdown-toggle` | `.vs__dropdown-toggle` |
| `.dropdown-menu` | `.vs__dropdown-menu` |
| `.clear` | `.vs__clear` |
| `.selected-tag` | `.vs__selected` |
| `.no-options` | `.vs__no-options` |
| `.spinner` | `.vs__spinner` |
| `.close` | `.vs__deselect` |
| `.active` | `.vs__active` |

## Internal State

**The changes listed below are very unlikely to break your apps** unless you've been hooking into 
vue-select internal values. [#781](https://github.com/sagalbot/vue-select/pull/781) 
(thanks [@owenconti!](https://github.com/owenconti)) introduced a number of optimizations to the 
way that the component handles internal state.

- `value`: the `value` prop is undefined by default. vue-select no longer maintains an internal `mutableValue` state when a `value` prop has been passed. When `:value` or `v-model` is not used, vue-select will maintain internal state using the `_value` property.
- `mutableOptions` has been removed in favor of an `optionList` computed property.

## Misc

- `fade` transition renamed to `vs__fade`
- Removed `a` element that was serving as the click handler within dropdown options