My CTE is set to prevent any modification to the source text (option "Edit source segment" deselected).
But, often when I try to copy a word (or part of it) in the clipboard to look it up in an external dictionary, below the selection cursor a small rectangle appears and the selected portion disappears from the source. It doesn't get deleted actually, for when I select the previous segment and return to the one in question the original text gets restored completely. Then, a second attempt to copy the same text portion is successful, that is without any modification to the source text.
Is the same happening to other CTE users?
> below the selection cursor a small rectangle appears
This is so because you have the Drag and Drop handling enabled (see it in the Edit menu). Either select your phrases carefully not to trigger the dragging action or disable this option.
Many thanks. Option disabled.