I'm running Robohelp 2019. We recently added a link to a website in one of our topics. Since then Robohelp creates a blank folder with that website name with an added app. at the beginning. It's not present in the content folder in the source files and we don't see it anywhere when the manual is open in the program but that folder is generated in the output files. It seems harmless because it's empty, we just don't know why it's happening.
What flavour of RH2019? Classic or New UI?
The new UI.
Is it also happening in the sample project? If so, then it might be a RH issue - patch up to lebvel 14 and try it there or grab the 2022 version and see if it persists in there. If it doesn't, then it's something with your project I would suspect.
Is it just to a regular url like www.google.com? Or to a specific file and if so what does that look like (perhaps it's to some sort of executable or funny file type that RH gets confused by?
And what output type - Frameless or Responsive - and skin. Theoretically that shouldn't make a difference but you never know.