Detached tabs don't work on Firefox

[fiatjaf]

Firefox webextensions framework has an issue with tabs that are detached from the main window. I know there shouldn't be the concept of a "main window" and that each tab is its own process, but for some reason there is.

What happens is that when the background script tries to query or send a message to a detached tab it fails.

I can replicate the bug many times but don't know how to fix it.