Review with custom Openings/PGNs/Games

[ChrompyCoder]

What is the idea?

Since we cannot store our openings/chess ideas on lichess online database/server, i propose we allow local storage which will be used to indicate, using arrow of different color than the computer review one, the next move according to the locally saved database along with computer analysis one.

Why?

When you click on review, it will be helpful to know where your prep ends and till where you could remember.
This can be used while setting up a new board, analysis using custom prep .

Things to keep in mind during implementation.

keep the data exportable.
import the data and analyse for faulty games while marking the arrows.
do not show arrow while a game is playing.

This feature can be introduced in mobile as the app can store/export/import/compute data which might be a problem for the website.
I might start working on it in the coming weeks so please criticize/ propose a better design asap

Thanks
@ChrompyCoder