1. 如果用户为金星以上级别的用户，且使用了Multi-Page Viewer(MPV)，进行提示，因为JHenTai当前不支持MPV
2. 里站画廊封面图无法访问，暂时全部替换封面图片url的host为ehgt.org

1. If user is at golden or higher level and uses Multi-Page Viewer (MPV), toast because JHenTai doesn't support it now.
2. Failed to load gallery cover image for exhentai without domain-fronting. Temporarily replace the 'host' field in all cover image's url from 'exhentai.org' to 'ehgt.org'