v3.26.1
Note 5 - Share-based Compensation - Stock Options (Details) - USD ($)
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
2024 Equity Incentive Plan [Member]    
Options outstanding, balance (in shares) 16,793,014 5,493,920
Weighted average exercise price, balance (in dollars per share) $ 0.21 $ 0.23
Options outstanding, Granted (in shares) 2,314,455 2,024,538
Weighted average exercise price, Granted (in dollars per share) $ 0.16 $ 0.28
Unvested (in shares) (4,957,864) (2,357,787)
Weighted average exercise price per share, unvested (in dollars per share) $ 0.2 $ 0.24
Aggregate intrinsic value, Vested [1] $ 0
Weighted average remaining term, Outstanding (Year) 9 years  
Aggregate intrinsic Value, Balance [1] $ 0  
Vested balance (in shares) 14,149,605 5,160,671
Weighted average exercise price, Vested (in dollars per share) $ 0.21 $ 0.24
Weighted average remaining term, Vested (Year) 8 years 10 months 24 days  
Options outstanding, Vested (in shares) 14,149,605 5,160,671
Weighted average exercise price, Vested (in dollars per share) $ 0.21 $ 0.24
Options outstanding, balance (in shares) 19,107,469 7,518,458
Weighted average exercise price, balance (in dollars per share) $ 0.2 $ 0.24
2018 Equity Incentive Plan [Member]    
Options outstanding, balance (in shares) 41,604,435 42,171,386
Weighted average exercise price, balance (in dollars per share) $ 0.19 $ 0.19
Unvested (in shares) (1,643,252) (2,942,091)
Weighted average exercise price per share, unvested (in dollars per share) $ 0.22 $ 0.22
Aggregate intrinsic value, Vested [2] $ 189,000  
Weighted average remaining term, Outstanding (Year) 5 years 7 months 6 days  
Aggregate intrinsic Value, Balance [2] $ 189,000  
Vested balance (in shares) 39,961,183 38,662,344
Weighted average exercise price, Vested (in dollars per share) $ 0.19 $ 0.19
Weighted average remaining term, Vested (Year) 5 years 6 months  
Options Outstanding, Exercised (in shares) 0 (566,951)
Weighted average exercise price, Exercised (in dollars per share) $ 0 $ 0.16
Options outstanding, Vested (in shares) 39,961,183 38,662,344
Weighted average exercise price, Vested (in dollars per share) $ 0.19 $ 0.19
Options outstanding, balance (in shares) 41,604,435 41,604,435
Weighted average exercise price, balance (in dollars per share) $ 0.19 $ 0.19
The 2007 Equity Incentive Plan [Member]    
Options outstanding, balance (in shares) 380,000 1,157,500
Weighted average exercise price, balance (in dollars per share) $ 0.63 $ 0.53
Weighted average remaining term, Outstanding (Year) 9 months 18 days  
Aggregate intrinsic Value, Balance [1] $ 0  
Options outstanding, balance (in shares) 380,000 1,157,500
Weighted average exercise price, balance (in dollars per share) $ 0.63 $ 0.53
Options outstanding, Expired (in shares) 0 0
Weighted average exercise price per share, Expired (in dollars per share)  
The 2007 Equity Incentive Plan [Member] | Minimum [Member]    
Weighted average exercise price per share, Expired (in dollars per share) $ 0  
Non Plan [Member]    
Options outstanding, balance (in shares) 14,039,129 15,687,642
Weighted average exercise price, balance (in dollars per share) $ 0.39 $ 0.4
Options outstanding, Granted (in shares)   32,143
Weighted average exercise price, Granted (in dollars per share)   $ 0.28
Unvested (in shares) (218,750) (218,750)
Weighted average exercise price per share, unvested (in dollars per share) $ 0.18 $ 0.44
Aggregate intrinsic value, Vested [1] $ 12,000  
Weighted average remaining term, Outstanding (Year) 1 year 7 months 6 days  
Vested balance (in shares) 13,820,379 15,501,035
Weighted average exercise price, Vested (in dollars per share) $ 0.39 $ 0.39
Weighted average remaining term, Vested (Year) 1 year 6 months  
Options outstanding, Vested (in shares) 13,820,379 15,501,035
Weighted average exercise price, Vested (in dollars per share) $ 0.39 $ 0.39
Options outstanding, balance (in shares) 14,039,129 15,719,785
Weighted average exercise price, balance (in dollars per share) $ 0.39 $ 0.39
Weighted average exercise price per share, Expired (in dollars per share) $ 0  
Options outstanding, Expired (in shares) 0  
Aggregate intrinsic value, balance [1] $ 12,000  
[1] Aggregate intrinsic value based on closing common stock price of $0.16 at March 31, 2026.
[2] Aggregate intrinsic value based on closing common stock price of $0.16 at March 31, 2026