Even though the Steam Guard mobile authenticator should be a good preventative measure against identity theft, there still are things how people can get around these security measures and breach your account – the most frequent occurence is people betting that the Steam account is not protected by...
If you find yourself stuck and your queue is not moving AT ALL for more than 15 minutes (approximately) this means that you actually errorred out of the queue, but simply didn't get the popup. Your queue will remain stuck at the same number indefinitely and you need to press the canc...