class app.views.Resizer extends app.View  @className: '_resizer'   @events:    dragstart: 'onDragStart'    dragend: 'onDragEnd'   @isSupported: ->    'ondragstart' of document.createElement('div') and !app.isMobile()   init: ->    @el.setAttribute('draggable', 'true')    @appendTo $('._app')     @style = $('style[data-resizer]')    @size = @style.getAttribute('data-size')    return   MIN = 260  MAX = 600   resize: (value, save) ->    value -= app.el.offsetLeft    return unless value > 0    value = Math.min(Math.max(Math.round(value), MIN), MAX)    newSize = "#{value}px"    @style.innerHTML = @style.innerHTML.replace(new RegExp(@size, 'g'), newSize)    @size = newSize    if save      app.settings.setSize(value)      app.appCache?.updateInBackground()    return   onDragStart: (event) =>    @style.removeAttribute('disabled')    event.dataTransfer.effectAllowed = 'link'    event.dataTransfer.setData('Text', '')    $.on(window, 'dragover', @onDrag)    return   onDrag: (event) =>    value = event.pageX    return unless value > 0    @lastDragValue = value    return if @lastDrag and @lastDrag > Date.now() - 50    @lastDrag = Date.now()    @resize(value, false)    return   onDragEnd: (event) =>    $.off(window, 'dragover', @onDrag)    value = event.pageX or (event.screenX - window.screenX)    if @lastDragValue and not (@lastDragValue - 5 < value < @lastDragValue + 5) # https://github.com/freeCodeCamp/devdocs/issues/265      value = @lastDragValue    @resize(value, true)    return