Browser freeze and code stop without exception

[AAlex-11]

This is my page factory, I expect 25 empty tabs

   Public Async Function EmptyPagesFactoryAsync(ByVal count As Integer) As Task(Of List(Of Page))
       Dim Pages As List(Of Page) = New List(Of Page)
       For i As Integer = 0 To count - 1
           Try
               ProxyCounter = (ProxyCounter + 1) Mod Proxys.Count
               Dim Proxy = Proxys(ProxyCounter)
               Dim ProxyURL = Proxy.Split("@")(1)
               Dim Extra = New PuppeteerExtraSharp.PuppeteerExtra
               Dim Browser = Await Extra.LaunchAsync(New PuppeteerSharp.LaunchOptions With {
                   .Headless = False,
                   .ExecutablePath = _config.GetSection("ChromePath").Value,
                   .Args = New String() {$"--proxy-server={ProxyURL}"}
               })
               Dim BrowserCredentials = New Credentials With {
                   .Username = Proxy.Split("@")(0).Split(":")(0),
                   .Password = Proxy.Split("@")(0).Split(":")(1)
               }
               Dim PageTask = Await Browser.NewPageAsync
               Await PageTask.AuthenticateAsync(BrowserCredentials)
               Dim cookies = JsonConvert.DeserializeObject(Of CookieParam)(File.ReadAllText("cookies.txt"))
               Await PageTask.SetCookieAsync(cookies)
               Pages.Add(PageTask)
               Browsers.Add(Browser)
           Catch ex As Exception
               _log.LogCritical(ex.Message & vbCrLf & ex.StackTrace)
           End Try
       Next
       Return Pages
   End Function

Proxy file read correctly, I'm sure. And proxies list is workable, because I use the same list in my other project based on TheArtOfDev automation, this means url and login/pass is correct. Chrome path also setting correctly, parameter also setting correctly --proxy-server==xx.xx.xx.xx:yyy. There are no any exception, but maybe I doing something wrong, because I see only one blank Chrome page after line "Dim Browser", than program stopped and line "Dim BrowserCredentials" never working.
Where is my mistake?

Interesting, if I downgrade PuppeteerSharp from last version to 7.10 and PuppeteerExtraSharp to 1.3.2 I receive another error in class AsyncMethodBuilderCore

What does it mean?