Note 8 - Equity Transactions and Stock-based Compensation - Summary of the Company's Stock Option Activity, and Related Information (Details) - $ / shares	6 Months Ended
Dec. 31, 2021
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)	(28,667)
Exercised, weighted average exercise price (in dollars per share)	$ 0.24
Terminated (in shares)	(15,033)
Terminated, weighted average exercise price (in dollars per share)	$ 0.33
Expired (in shares)	0
Expired, weighted average exercise price (in dollars per share)	$ 0
Balance (in shares)	4,437,666
Balance, weighted average exercise price (in dollars per share)	$ 0.35
Exercisable (in shares)	3,365,766
Exercisable, weighted average exercise price (in dollars per share)	$ 0.24

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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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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