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Re: @TimidScript:
OK, I found the reason.
An other pixiv script is incompatible with Pixiv++, and everything works fine after removed that script.
Sorry cause your inconvenient.
Thanks for your update!
It looks very well but somehow not work on member_illust.php (autopage seems fine but display and filter option not work) in version 3.1.57 (TEMPORARY UPLOAD AREA).
Just for your information :)