Hi, thanks for this! Not sure if you're aware that clicking Australia goes to American Samoa, similar issue with some others that I encountered (Bahamas -> Burkina faso).

The fact he got locked up?

Issen https://news.ycombinator.com/item?id=44387828

https://www.languagereactor.com is something similar to Yabla I think... But you can use it indefinitely and subscribe if you need the premium features.

I would argue that it's harder for me to decide how easily I recalled a word and decide between a few loosely defined levels as to which one I should choose than to apply a simple algorithm.

If the window loses focus it would be able to pause automatically. If you are distracted another way, no big deal you will see that word again soon and unlikely to keep getting distracted on the same word. The benefits would outweigh the odd misfire.