Pressing enter in a<s-text-field>doesn’t emit a submit event. How is this even possible? This is a basic HTML feature? And it worked in the React version of Polaris.
This is a known issue (Form submit not working on Enter key with <s-text-field>). It sounds like it’s on the radar of the polaris team already!
Keep in mind that the library is very new, so there will be teething problems.
This library seems to be all teething problems. I think I stay with Polaris React for as long as possible. So many things that either are buggy, aren’t implemented, and/or aren’t possible to hack in with this shadow DOM stuff.