Practice all words not just random or weak ones
I want to practice every single word that I learned not just random set or weak ones. Even if it's almost infinite number of questions I'd still prefer to see that I've finished reminding myself words that I have learned previously and that I can see how much more progress do I need.
This is absolutely possible, but you should understand that you'll have to practice for a long time to cover every single word. For example, you know 165 German words by now; about 10 words are refreshed in every practice session, so you'd probably have to do 16 or 17 practice sessions - maybe more if different forms of the same word are counted as different words, maybe less if some words get strengthened without being targeted for practice.
A couple of weeks ago, I made a "big practice day" and refreshed every single Spanish word out of 400+ that I had learned by that time.
What I did:
I opened Vocabulary in a background tab and sorted all the words by strength so that the weakest ones would be on top. In my main Duolingo tab, I began to do timed practice. I refreshed Vocabulary page from time to time and adjusted the sorting. After a while I noticed all my words were at 4 bars of strength.
Then I sorted Vocabulary by "Last practiced" so that the less recent words would be on top. I continued practice. Duolingo mostly gave me words I had not seen for a long time.
After I earned about 400 skill points that equals to 20+ timed practice sessions, the less recently seen word in my Vocabulary was marked as seen on the same day. So I really had gone through all the words.