Note 8 - Equity Transactions and Stock-based Compensation - Summary of the Company's Stock Option Activity, and Related Information (Details) - $ / shares	9 Months Ended
Mar. 31, 2022
Balance (in shares)	3,916,666
Balance, weighted average exercise price (in dollars per share)	$ 0.26
Granted (in shares)	564,700
Granted, weighted average exercise price (in dollars per share)	$ 0.97
Exercised (in shares)	(29,667)
Exercised, weighted average exercise price (in dollars per share)	$ 0.25
Terminated (in shares)	(30,633)
Terminated, weighted average exercise price (in dollars per share)	$ 0.30
Balance (in shares)	4,421,066
Balance, weighted average exercise price (in dollars per share)	$ 0.35
Exercisable (in shares)	3,404,799
Exercisable, weighted average exercise price (in dollars per share)	$ 0.25

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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