The simplest I can think of is just to move the directory (and suffer the pain of pulling in updates from upstream), or rename the file to include "1.0" or something (and suffer the same pain).

Maybe:

`/static/js/embed.chart.make-1.0.js`
`/static/embed/iframe-1.0.html`

Then any backwards-incompatible change requires a rename.

But all that said, if a change requires a rename/version bump, then do we need to both about doing it right now?

Let's just keep it as is and deal with that problem later. I can't think of a solution now that will save us pain in the future.