Note 11 - Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Jun. 30, 2023
Deferred tax assets:
Net operating loss carryforwards	$ 18,900	$ 17,920
Tax credit carryforwards	1,800	1,530
Lease liability - current and non-current	63	128
Unrealized loss on securities	247	305
IRC Section 174 R&D Expense Capitalization	2,107	1,061
Accrued expenses and other timing	310	143
Stock-based compensation	63	111
Property and equipment, principally due to differences in depreciation	0	0
Total gross deferred tax assets	23,490	21,198
Less — valuation allowance	(23,444)	(21,064)
Net deferred tax assets	46	134
Deferred tax liabilities:
Right-of-use assets	(25)	(55)
Property and equipment, principally due to differences in depreciation	(21)	(79)
Total gross deferred tax liabilities	(46)	(134)
Net deferred tax assets	$ 0	$ 0