I received several emails yesterday in regards to a problem with Embeds after users update Stacks to v4.2.1. The bug appears to be in Stacks itself. It prevents users from being able to drag an Embed from the Alloy Editor on the user’s site into RapidWeaver to embed it into the project file.
I’ve contacted Isaiah over at YourHead Software and he’s going to have a look at it and fix the problem, as it appears to be a bug in Stacks itself.
If you’re having this problem with Alloy Embeds after republishing your site using Stacks v4.2.1, you’ll want to downgrade Stacks to v4.2.0 then Republish All Files from RapidWeaver. This should allow you to once again drag and drop Embeds from your Editor into your project file in RapidWeaver.