I've paraphrased these notes from one of my posts in the kobopatch request thread. I may need to refer to them later in this thread.
Important general info about customising font-family in the Kobo GUI. It is particularly relevant to users who mainly read standard epubs rather than kepubs.
After a full reboot, as far the GUI is concerned, the Kobo only has immediate access to a limited number of its built-in fonts, Georgia, Avenir and possibly one or more of the CJK fonts. The rest of its built-in fonts and all your sideloaded custom fonts are only loaded "as necessary". I don't know the exact rules, only what I've observed.
After a full reboot I've always found that the following will force the Kobo to access all fonts. You won't have these problems if you only put the Kobo to sleep.- Open any kepub. It's as easy as that for users who only read kepubs.
- If you open a standard epub and you don't see the custom font you were expecting (in the GUI not the book's text)
- Press the [Aa] font menu button. You don't need to do anything else, just close it again.
- If you still don't see the font, force the Kobo to re-render by paging across a chapter file boundary, then page back again. Or, closing the book and opening a different one might work, too.
N.B.: *** Update for firmware 4.21.15015+ ***
It is now possible to avoid having to do the above after every reboot. See the
*** Update in the
post #63 Summary for more details.