Thanks for your report. We will check it... it's very strange that addon keeps caching capcha image as we tried to make URL random and it should not be cached for sure. It could be some issue with Firefox itself as FF56 is experimental. We will check everything again from our end.

Thanks for your review and trust in our service. Could you please tell us what we should add to our tool to get all five stars from you? =)

Could you please tell us what we should improve to get five stars from you? =) We are doing our best to make tool as useful as it could be. However, we may miss something important. Your opinion is very important for us