You can use this extension to convert the ugoira on Pixiv to GIF or WebM file, or pack the images of manga to download or save novel as epub. You can feel free to open issue on GitHub if you have any questions. There is a power Pixiv downloader Pixiv Omina has been released! It's easy to use and it has plenty features, you should give it a try. Github: Pixiv Toolkit: https://github.com/leoding86/webextension-pixiv-toolkit Pixiv Omina: https://github.com/leoding86/pixiv-omina