Note 5 - Stockholders' Equity (Deficit), Stock Option Plans, And Stock-Based Compensation - Summary of Common Stock Reserved for Future Issuance (Details) |
Jun. 30, 2025
shares
|
|---|---|
| Shares underlying outstanding warrants (in shares) | 81,645,868 |
| Total common stock reserved for future issuance (in shares) | 91,923,733 |
| Stock options outstanding (in shares) | 3,306,278 |
| Equity Incentive Plan 2020 [Member] | |
| Total common stock reserved for future issuance (in shares) | 6,971,587 |