Swipl.css is 404ed

I’m getting a 404 on the swipl.css file, so the whole swi-prolog.org site is looking fairly unstyled.

Weird, for me it looks normal, an the referenced swipl.css (https://www.swi-prolog.org/css/swipl.css) is where it’s suposed to be.
Maybe it got fixed fast.

It appears to be working for me now too. Fast fix I guess.

I’m afraid not. This has happened a few times. Seems like one of the backends misbehaves sometimes and the CDN things the CSS file is missing. After a cache invalidation time it will retry to access the backend and the problem is (usually) solved. I’ll check the log files.

In the meanwhile, the work-around is to access one of the two backends directly: https://eu.swi-prolog.org or https://us.swi-prolog.org. Please only use these for bypassing emergencies and do not advertise them as `better’ alternatives. Most of the times the CDN is more reliable and is a stable location. The backends can be accessed directly, but should be considered less stable and may at some point deny direct access.

The log files tell me that both backends occasionally claim /css/swipl.css to be non-existent. Now the question is why

Fixed with SWI-Prolog 8.1.18 (introduced in 8.1.11). Thanks for reporting. The underlying issue was rather critical.