@KevinH: Thanks for pointing me to the option to turn on JavaScript (good security behavior
) which was not implemented for Book View (bad security practice
) and yours suggestion to implement PageEdit as an external (X)HTML editor to restore the old View Book functionality. Current Sigil content with include non-saved changes can indeed displayed and saved in PageEdit.
@Vroni: I did a lot of investigation to see how to implement Responsive Mobile frame works like Bootstrap 3 or 4, Materialize can be ported to EPUB. I get the best result on different tablets and Android telephones with the free GitDen reader which has also a free Apple version (not tested by me).
I see the best result with CSS only frameworks which are designed to work with different Browsers. Sadly all browser tests never show results for EPUB. Therefore you need to test what is working as expected and what is not working at all within Sigil and the E-reader. Especially those frameworks who have webkit replacement for not implemented CSS function gives the best results in GitDen. I have good results with Skeleton version 2.0.4, which include a normalize.css to overcome all kinds of browser issues. I drop font loading from Internet or if needed like the Awesome or Google font, I store a modified version into the EPUB.
@DiapDealer: I’m aware of the fact is that it is the development team or developer to accept, reject and prioritize bug fixes, new options, how they follow the standards for HTML5 and JavaScript, and which options are set for an out-of-the-box setting. In the many years of discussion you refer to, I saw therefore no reason to add something meaningful to it.