Thanks for this immediate testing.
I inspected my file - even with a Hex Editor - no sign to any invisible character.
File was also saved in UTF-8 Format (actually using VS Code) - but also checked with other editors.
However when trying all this I noticed that it worked with a different filename of the .map file (so e.g. sp_test.map was working).
Finally simple renaming my original sprinkler.map to sprink.map made it working as well.
I do not understand such a behaviour… maybe something todo with internal caching in openHab?
But so far issue solved.
Thanks