Users of my Discourse site frequently paste URLs from the web documentation for the API of software they use. The URLs for pages in the API docs often have the tilde character ~ in them. When such links are pasted into the new rich text editor composer window, the tildes are improperly escaped. So, a URL like this:
https://help.solidworks.com/2023/english/api/sldworksapi/SolidWorks.Interop.sldworks~SolidWorks.Interop.sldworks.IFeatureManager.html
gets mangled to this:
https://help.solidworks.com/2023/english/api/sldworksapi/SolidWorks.Interop.sldworks\~SolidWorks.Interop.sldworks.IFeatureManager.html
Note the extra backslash before the tilde. The same link pasted into the Markdown composer window is not mangled.