Hi!
This has started to happen with notifications:
And it stays there in the way. 
Additionally, the old issue still exists. Not sure if it has to be this way… Editing a Layout on a certain product or post doesn’t go into that product or post, but says that no suitable preview is available, so the post type and the specific post need to be dialed in manually.
Thanks! Good point here. That message lasts 15 seconds allowing enough time to read it. I’ve just made it dismissible so you can close it out quickly.
As for the other issue, yes I’m aware of that one. It’s something we’ve not worked out yet. The best we have at the moment is that it should save your preview URL to the last thing you used on a particular asset.