HF21 is HardFork upgrading of the Steem blockchain. It will happen on the 27th of August 2019.
The blockchain integrity is the pride of Steem. As a cryptocurrency, Steem exists because the blockchain exists, thanks to cryptotechnology.
Please, click the texted blue bar just on top of your dashboard or click the link below to read more about the HF21 to know what to expect.
https://steemit.com/hf21/@steemitblog/hardfork-21-survival-guide!