Can't see embed code in editor

Hi!

After upgrade to update 304 we cant see the source code for embed and iframes that we published in the editor before the upgrade. The page can still show the iframe and embed content but its invisible in the editmode, when we hit the view source button in the editor the popup is blank. If we put new embed or iframe code in the editor it works, Then we can view the source in the editor and the embed code shows in the popup. 

Any clues on what's going on?

We are running: 

• EPiServer.Forms.UI 4.27.0.0
• EPiServer.UI 11.23.6.0
• EPiServer 11.14.1.0
• EPiServer.Cms.AspNet 11.14.1.0
• EPiServer.XForms 1.0.3.0
• EPiServer.LinkAnalyzer 11.14.1.0
• EPiServer.Cms.Shell.UI 11.23.6.0
• EPiServer.Search.Cms 9.0.3.0

Best regards

Kristian