: Pirated versions frequently suffer from bugs, such as the inability to save transparency or files opening in "Restricted Mode" because they lack a valid system ID. How to Get Paint Tool SAI 2 Officially
Often, the "full version" is actually a leaked beta from 2019. It is unstable, crashes constantly, and lacks the features of the legitimate 2024/2025 updates (like the ruler stabilizer and improved text engine).
If you want a stable, safe experience, the only recommended method is through the official developer,