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@ganbold Anki is great for building vocabulary!
By using Rikaichamp to add words I meet in my daily life, I am essentially word mining.
If you don't live in Japan, you could try sentence mining, which is similar. This video seems like a good introduction: https://www.youtube.com/watch?v=B60cj69MSmA
Note that you need around N4 grammar+vocab level before it makes sense to sentence mine, you don't want to get stuck having to look up every single word you see. Otherwise a single episode may take an hour or more to finish, which is hard.
@ganbold https://foosoft.net/posts/passing-the-torch-to-yomitan/
Actually, yomitan seems to be a good alternative (to rikaichamp) nowadays.
I double-checked my browser and it seems I'm still using yomichan (which is deprecated...)