[Resolved] formatting markers in original text which should not be there

#1 "How did you "break" the translation segments? Did you do this in the source or in the target language segment, and how?"

---> I did this by clicking on "translate automatically" to automatically translate the string, it adds the formatting markers automatically.

You can also add it manually by writing <wpml_break>.

#2 "I may have to go into the code to remove the line breaks in the original segments that should not be there - how do I do that?"

---> That is correct, WPML has not added these line breaks it simply detects what is in the source content.

UPDATE:

Indeed, there is NO line break in the default language.
There is a chance this used to be there before and it was removed leaving the advanced translation editor "stuck".

To resolve it, we need to trigger an update.

1. I edited the page in Colibri editor
2. added an extra period . something small but enough to trigger an update (removed now)
3. The line break marker is no longer showing in the translation editor.

#3 "Another longer-term issue is that I do not want to use automated translation because it simply is not good enough"

---> You have 2 options.

1. Don't use the automatic translation feature and manually add the translations.

"Translate all content automatically when the editor opens" is disabled and "translate everything" mode is not enabled either

2. Use the Classic translation editor instead which does not use the automatic translation at all.

See the following documentation:
https://wpml.org/documentation/translating-your-contents/using-the-translation-editor/