That's really cool
Chess Memory Trainer

This is a great web app.
Could you, please, make an option for dark mode and a button to play again with the same settings?

How does this improve your chess? 🤔
The goal is just to have fun and challenge yourself!
I have made a game that is the same as #1 that is an improvement. do check it out! It is on:
https://thememorychess.com/

Chess is a memory game, so this approach to learning it should work.
Yes it is but there are positions that are not necessary because even the grandmasters would be having a hard time memorizing a position that is not theoretically possible... I wonder why...
Note: The Chess Memory Trainer do play all theoretically possible positions so it's good... Sorry for false alarm...
I made some minigames to test/improve your chess memory.
Link: https://chess-memory-trainer.web.app
There are four in total, in which you have to:
#1. memorize a position in 30 seconds;
#2. memorize a game being played on the board;
#3. memorize a game notation;
#4. follow a game notation in your head and set up the final position.
Also, you can select the number of pieces/moves you'd like to memorize and for minigames #2 and #3 you can either memorize all of the moves in one go or one by one.
That's it, let me know if you enjoyed it!