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Their proprietary counter is giving false numbers on the amount of shares. This can be shown from the website replays (I'm not seeing even half of the people clicking the button). Other than that, the button works just fine and does its job.
Thanks for your review, apologies for any share count error you have encountered. We'd be happy to look into this more deeply, please send us an email at email@example.com and we'll try to reproduce your issue and get to the bottom of it.