I cannot drag an embed-stack into RW - SOLVED

The option of using Embeds is a favorite option of Alloy. I use one on most of my webpages. So till now it worked fine.

But at the moment I cannot drag and drop the embed-stack into RW.
I tried different browsers, but alas.
The mouse/cursor isnot able to pick up the stack.

Maybe something isnot right in the url or …???

I found the source: I have used a lock on the page, to prevent drag and dropping : )