I wrote a blog post about the modifications of the Kobo e-readers to make them more pleasant to use
the text is in French but you should understand it using an automatic translator
if some passages are not understandable, don't hesitate to send me a message and I'll try to explain it to you :)
https://oniricorpe.eu/log/tech/2022-10-08_kobo-hacks-mods/