BEXT: Popups can't be dismissed occasionally

Created by: ryankscott

In some circumstances the code-intel popup can't be dismissed in GitHub.

Steps to reproduce:

1. Go to https://github.com/sourcegraph/sourcegraph/pull/38209/files, then go to line 43
2. Click on "Go To Definition” for Context as part of *cli.Context.
3. Click on the Browser back button

Now the popup can’t be dismissed.

Loom of the behaviour