Ability to Redo a Lesson
Please can we have an ability to redo a lesson - sometimes I feel I have missed something important or would like to strengthen words / syntax,
As a workaround you can actually PRACTICE earlier L1-L4 crown skills:
Maybe the available Tampermonkey userscripts and browser addons/extensions - to stay within proper spaced repetition (SR) next intervals - help you a bit better to practice earlier Non-L5 skills?
It has been 1 year and 4 months since the crowns were rolled out.
Honestly, I do not think that we will see this old lesson feature re-engineered anytime soon.
Crowns have DYNAMIC "crown sessions" (=lessons), not fixed ones.
You can replace ANY (lesson) number behind the skill and still get not a specific one but the sessions are dynamically polled and incremented internally.
This last update even increases the auto-leveling to the next crown level (e.g from L1 to L2): https://forum.duolingo.com/comment/32313440/Word-based-Progress-Update
I have not seen the backend code, but my feeling is, that the current implementation of the "crown sessions" (since April 2018) is probably very far away and done in a (very) different way so it will not be too easy for the developers to give support for redoing a FIXED lesson number.
However, you must be aware that the old PRACTICE strength system (internal strength calculation, words decay) got more and more buggy in 2019.
The backend / API seems to be broken either completely, (partly) turned OFF for several skills or probably has received some new bugs because of the late changes on the web code.