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I've never seen a manga with so many full-color chapters. I believe for Fuuka, Kimi no Iru Machi, Suzuka (all of them by the same author), and also many other manga only have a few pages of color manga when there is a color edition.
Yet, from chapter 116 to 134 (as of writing), all of the chapters have another version that is in full-color. From my perspective, this is very unusual. I understand that it is a very popular manga, but manga I listed above and other manga are just or even more popular, but none to my knowledge have had this many strings of full-colored publications.
Is there a reason to this or did the author/artist just have a lot of extra time to devote to coloring in the manga?