@rubyFeedback please note that you can attach images also directly to the issue. This saves us from opening thrird party websites just to see a small image. Thank you.
I agree with @elextr, the described completion behavior is caused by the `Preferences->Editor->Completions->Autocomplete all words` option and because the completed text is also present in the very same document. This is how this feature is intended to work.
I will close the issue.