Downloading favicon for book is not always working for Apple (iOS/macOS)

[BPerlakiH]

Similarly to the former issue: #1180

This is still not working for Apple.
There's actually a regression in this regard, please see the context of the issue described here:
kiwix/kiwix-apple#1359

Context

We have this call:

book->getIllustrations().at(0)->getData();

It suppose to return the favicons image data. We are calling it as part of fetching the catalog. In reality, it not always returns the data. (eg it is working for DWDS) but not working for ZIM files in the current catalog. It wasn't returning any data as of libkiwix 14.0.1 either for the current catalog.
(see related past issue: #1180)
I am not sure if this was meant to be fixed in libkiwix 14.1.0 or not, but:

• we still see no image data returned on Apple side (length 0) for current catalog items
• trying to access this data is taking a whole lot more time than it used to

[kelson42]

@veloman-yunkan We really to need to have this workind, tested and docuemnted properly.

[BPerlakiH]

@kelson42 @veloman-yunkan There's an update to it.
I've just tested this on custom apps with the DWDS zim file, and it is returning the required data, so it very much seems that it is something related to the ZIM content (or maybe version).

[BPerlakiH]

@veloman-yunkan please hold on with trying to fix it, it might be something on our side after all...

Will update soon.

[BPerlakiH]

ok, so I got it now.

I think the problem is that is does have the data, but those favicons are downloaded one by one during parsing the catalog, that's why it is taking so long to process the whole catalog.

So in short, there's nothing wrong on the libkiwix side, we just should not call this favicon download function in a loop on 3000+ elements.

Sorry for the confusion, closing the libkiwix side of the issue.