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For mine HBIT , You can comment or reply with !hivebits or !HBIT Then you will receive 0.9 HBIT and the account of post will receive 0.1 HBIT.
if you comment your post , you earn & mine 100% of HBIT and will receive 1 HBIT.
At first, this operation could have been done, but due to the significant reduction in the price of HBIT, now it seems that the donation has stopped. But it still exists as Hive-Engine Tip Tokens!