1- since you go through the first pages of the comic quite quickly, I'm not sure loading 4 pages ahead instead of 2 would change anything (sinc you read them faster than Ubooquity can load them anyway).

2- already planned, but it takes time to implement

Ubooquity 2.1.1 released with CBI support for CBZ (not CBR, as I couldn't access the comment for this type of archive).

Deactivating the server-side bookmarks was a way to give me information on your problem. I would of course prefer to understand and fix it.

Now I know the slowness is caused by the bookmark saving to the server. I need to find why.

If you go back to your initial configuration (uncheck "Store bookmarks in cookies instead of the server"), does the slowness happens for files other than PDF shared in the "books" section ? (as opposed to PDF shared in the "comics" section, CBZ, CBR and Epubs) ?

Also, can you check if you have errors in your logs when the slowness happens ?

For now I prefer to focus on other features than working on a closed, undocumented format.

As a workaround you can quite easily convert your mobi files to epubs using Calibre for instance.

No space left on device

Your disk seems to be full.

@ubooquity_37b645 : sorry for not answering, your message came at a time I had not much time to answer, I forgot to go back to it afterwards.

Both of you: I have been able to reproduce the issue with PDF shared in the "books" section. I'll fix it. Does it happen in other cases for you ?

Could you activate the "Store bookmarks in cookies instead of the server" option in advanced settings and try again ?

It is. :)

Look at the "exclusion pattern" option in the advanced settings.

That's weird: it's as if one class of the PDF library used by Ubooquity was missing, but the other (from the same library) were here.

I have to admit I have no idea how this can happen.

Ok,the classe is accessible, but something goes wrong during the fonts loading.

You wouldn't happen to have a "Caused by" stack trace in your logs just below the one you posted ?