Raven.install() never completes in Firefox (Chrome extension for gmail)

Basically - title.

We have a Gmail extension where Raven is working in Chrome, but when running the same code in Firefox, the Raven.install() never completes, and blocks the rest of the injection script we have to initialize the extension.

Does anybody have any idea what would cause this? The offending line is simply


There were only two other topics on this I could find, neither with any information about how to solve.