Half working with imported ebook on kindle

[Adhgqef7575]

Hello,

I have a kindle Oasis 10th Generation, firmware 5.17
I've managed to use the fonts for books I have officially bought from Amazon

However for those I have imported without DRM I ran into some issue.
I found out that by editing the CSS code with Calibre I've been able to force the change of font.
How I did it : by commenting all the lines that include a font-family.
Exemple : /* font-family: "Georgia", "serif"; */

However it still doesn't fully work. The font does change (I can clearly see the difference with the Fast Mono) but the bold part is not there.

I also only imported the 4 .TFF version to test and force it in the css, but it doesn't work.

I'm out of ideas.

(At least it works on purchased books which is already great !)

[Born2Root]

Yes, what you describe is unfortunately a known problem with the Kindle eReaders.
They behave quite different, depending on the model.

There is still an ultimate sledge-hammer solution 😄

That means you do not directly use the font, what would be the most elegant way.
Instead you can "hardcode" the speed-read formatting into the eBooks.

One user wrote a little python script to apply the fast-reading feature directly in Calibre.
Until now that worked for all devices that made problems...

Here is the link to the script repo.
https://github.com/giutala/calibre_bionic_converter