I have a bookmarklet for reddit / saidit that automatically populates the url and title in the submit form. It would be neat if matrix supported this in some way to ease in submitting new links.
bookmarklet:
javascript:(function () { window.open( '[https://www.saidit.net/submit?title=](https://www.saidit.net/submit?title=)' + document.title + '&url=' + document.URL, '_blank' );})()
Some parameters you can use are title, url, topic, sub. All are optional. Sub and topic are the same thing but you have options. I don't know if it 100% what you were going for but it will auto fill the form. That gives you a chance to fill in a sub if your parameters don't have it.
Would you mind testing it. If it works we should share your bookmarklet.
https://lab.gvid.tv/x0x7/ShareMatrixBookmarklet/src/branch/main/README.md