Doulingo says it can also be translated with "Je n'aime pas cette pensée" - is that right? I would say that pensée means "thought" more than "idea". I know the meaning is the same, but if looking for the precise translation?
I was not fully aware of this rule. As "cette" will never appear before a masculine noun, does this mean that only "ce" can become "cet" and that "cette" will never become "cet"? This would seem to be the case.