prefs.config location and where u save hightlight ?

[ilovejs]

When I open with another pdf viewer, highlight is not write to pdf file.
So, how can this feature be done ? / is this supported ?
If not, where is the location u saved highlight marks ?
where to have prefs.config file when using Ubuntu appImage release ?

Most of software on linux do not save inside pdf only few do. e.g. Okular
but it's not very capable.

[ahrm]

We don't modify the PDF files in sioyek. The highlights are saved in a file name shared.db (it is a raw sqlite database). We do have a command to create a new file with annotations embedded called embed_annotations.