Note 12 - Share-based Compensation - Assumptions (Details) - $ / shares	6 Months Ended	12 Months Ended
Dec. 31, 2022	Dec. 31, 2023	Jun. 30, 2022
Weighted average fair value (in dollars per share)	$ 0.26	$ 0.32	$ 0.55
Options issued (in shares)	4,235,000	21,665,273	3,269,100
Expected term (in years) (Year)	5 years	5 years	5 years
Minimum [Member]
Exercise price (in dollars per share)	$ 0.33	$ 0.24	$ 0.28
Risk-free rate	2.97%	3.84%	0.73%
Volatility	100.00%	93.00%	99.00%
Maximum [Member]
Exercise price (in dollars per share)	$ 0.36	$ 0.69	$ 0.79
Risk-free rate	3.00%	4.46%	3.24%
Volatility	101.00%	108.00%	100.00%

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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