Common stock - Public Offering of Common Stock (Details) - September 2021 - USD ($)	Sep. 24, 2021	Jun. 30, 2022
Warrant to purchase shares of common stock	8,771,928
Exercise price of warrant	$ 0.001	$ 0.001
Common Stock.
Common stock issued	22,828,072
Issue price	$ 2.85
Net proceeds from issuance of common stock	$ 96,828
Underwriters' exercise \| Common Stock.
Common stock issued	4,740,000

Exercise price per share or per unit of warrants or rights outstanding.

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