Amazon's Send to Kindle extension is Chrome-only, so I built one for Firefox. ArticleFerry makes a clean EPUB of the page you're reading (cover, title/author, images) without any server or account, then opens your mail addressed to your Kindle so you attach it. The EPUB works on Kobo/KOReader too.

Disclosure: I'm the developer. It's free; not open source (yet), I know that matters here. Happy to answer anything about permissions or data. Feedback on sites that break is very welcome.

Nice, would be cool to see Crosspoint support too!

thanks! ArticleFerry already saves a plain EPUB file, so it should work with CrossPoint today: save the article, then on the reader open File Transfer, join your wifi and upload the file from the page it shows (or copy it to the SD card). I haven't tested it on an X4 myself, so if something renders oddly let me know. sending straight to the reader over wifi would be a neat addition, I'll note it down.