I am not sure (as still a newby) but believe I found a nasty little defect in the sitemap editor. At least I was finally able to reproduce it:
I have OH3 installed on a Raspberry 3, everything super so far. But then I realized I don’t have to use the graphical UI for defining sitemaps, but can switch to a code mode instead. So I started editing my configuration, but every time I safed it that resulted in my sitemap not being accessible anymore - e.g. the iOS App that I use it for threw back an 404, and also the Basic UI did’nt want to load it anymore.
Initially I thought I was doing something wrong, and after this happening a couple of times (and me always having to start from scratch again) I just didn’t use the code editor anymore. Until today - and et voila - same problem again.
So I started digging depper, and - by trial and error, copying code in and out - finally found that there is one specific setting causing this: in the slider component, there is the “switchEnabled” option. For some reason, when this is set to ON, and you manually change code, this is causing problem. To be clear - as long as you only turn this option on in the UI, nothing bad happens. It is only when you change the code manually and safe it.
Since I don’t know how to raise this defect I am just publishing it here, hoping it reaches the right people so it gets correct. Happy to help of course if necessary.