Based on the mention of auto-dark-mode, probably. We put some effort into thinking about how to do dark mode right and integrate with system settings - your usual website hack of an invert toggle is wrong, but the correct auto/light/dark tri-state toggle is not obvious.
I'll have to look at the strategy you took. Thanks for the article! I now also remember the mention of Mnemosyne, which was the first SRS app I ever used (got me through medical school!). Now using RepetitionsApp x years.