Thank you for thinking of supporting it. There's no paid tier and no add-on held back, and that won't change.
A way to donate is on its way. Until then, these help just as much:
- Star the repository on GitHub, so other people find it.
- Tell someone who keeps dragging windows around by hand, or fighting their scroll direction.
- Report what's broken. Settings → General → Diagnostics… gives you a report to paste into an issue, or email hello@vellund.com.