OAuth authorize javascript error with System.Windows.Forms.WebBrowser

javascript error at https://d3oaxc4q5k2d6q.cloudfront.net/m/3d70c2b99510/dist/main.js

$authorizeUri = "https://bitbucket.org/site/oauth2/authorize?client_id=hmepwfg9wqvXypWYAW&response_type=code"

Add-Type -AssemblyName System.Windows.Forms
$OnDocumentCompleted = {
  if($web.Url.AbsoluteUri -match "code=([^&]*)") {
	$script:AuthCode = $Matches[1]
	$form.Close()
  }
  elseif($web.Url.AbsoluteUri -match "error=") {
	$form.Close()
  }
}

$web = New-Object System.Windows.Forms.WebBrowser -Property [~legacy-bitbucket-user]
$web.Add_DocumentCompleted($OnDocumentCompleted)
$form = New-Object System.Windows.Forms.Form -Property [~legacy-bitbucket-user]
$form.Add_Shown({$form.Activate()})
$form.Controls.Add($web)
$web.Dock = "Fill"

# Request Authorization Code
$web.Navigate($authorizeUri)
$null = $form.ShowDialog()