The workaround
Here I describe how I dig out of a tight corner to get tweets properly expanding in Electric River. Glad to get this working!
by Dave Winer Thursday, March 30, 2017

Re the problem I reported yesterday.

The problem shows up in Electric River, which loads from a file:// address. The reason I do that is that I don't want to turn on the HTTP server in River5, so the user on the Mac doesn't get the geeky dialog confirming that they want to run a server. So I couldn't solve the problem that way.

Instead, I added a hook in the code that displays a tweet in a river, which is deeply buried in the code, it's part of the nodeStorage API. Of course I didn't want to put the hack at that level, there are too many other places that could break. So I added a callback. It just substitutes // with and it works. Hot damn.

Here's a quick video that demonstrates.