Just activate comic sharing in the preferences.

Well, according to the error message, your browser tries to connect to Ubooquity using HTTPS instead of HTTP.

But I don't know why. :(

That's a bug I plan to fix: Ubooquity uses the comic title to sort issues, but when the title is not available in the metadata, it uses the file name. Hence the inconsistent sorting.

I plan to add an option allowing to choose between title and filename sorting.

The 504 HTTP error is a gateway timeout. It mean that one on the servers (proxy) your request goes through is timing out.

This can mean that Ubooquity is unreachable or veeeeery slow, or that there is a problem somewhere else on the chain of servers crossed by your request.

For OPDS (and OPDS only, other parts of Ubooquity manage authentication using a different method), Ubooquity uses Basic HTTP Authentication.

This authentication method is made mandatory by the OPDS specifications, that's why it's different from the method used elsewhere in Ubooquity.

Let me know if you have specific questions about this.

I am entirely dependent on JUnrar to extract files from RAR archives. And as you have noticed, JUnrar is not maintained anymore (and I couldn't find any alternative).

So there is not much I can do, apart from fixing it myself (which I won't do) or advise you to convert your files to a more sensible format, like cbz.

I opened your file with an hex editor: there is no character (BOM or other) before the usual XML content.

I also launched Ubooquity using your file, without triggering any error.

So I still have no idea of the cause of the problem.

Ok, just found it: the problem comes from the "#" character in your folder name.

I don't know why (problem is inside Jaxb, the internal XML library used by Java), but I was able to reproduce the problem that way.

Just remove the "#" and it will work fine

Yes, sorry.

Sumatra is written in a completely different language, so it wouldn't help, but thanks. :)

As for the work required for the modification: it's done in Javascript (not Java), a language I'm not an expert in and which is one of the most painful to use (but when you write code for browser you don't have a choice).

Breaking things written in Javascript is quite easy, that's why even simple features take time when they are done in this language (although Angular helps a bit, for those who are familiar with the Javascript ecosystem).