What is the most common UI you are using

Yes, agree. There are too many slightly different ways in MainUI to get text definitions of settings in:

  • Items:
    explicit import function for items
    copy in text definitions generates the items, channels and metadata, only import
    code tab shows YAML
  • Sitemaps:
    ability to copy textual definition into code tab
    switching to code tab shows textual definition and JSON, no YAML
    textual definition is generated from UI definition
  • Things:
    no import possible
    code tab shows YAML
  • Transformations:
    only show textual definition of transformation, format the same is in file definitions
    no code tab
  • Persistence:
    no import of textual definitions
    code tab shows YAML
    persistence strategies defined in text files are visible read only in code tab as YAML, and can be copied in the code tab to create pure UI definitions (open the persistence definition, copy the YAML, remove the persistence file for the persistence service and create the persistence strategy for the service in the UI, copying in the YAML)

This is something that may be candidate for some standardization also in the context of RFC: YAML configuration · Issue #3666 · openhab/openhab-core · GitHub.