Containerized tabs not restored when restarting Firefox

[alexozer]

When I change the container of a tab using a shortcut from this extension, if I restart Firefox, it appears the tab is restored in the default container instead of the correct container. However, if I change the container using native Firefox functionality by right-clicking a tab and choosing "reopen in container", the tab is restored to the correct container when I restart Firefox.

I don't know if it makes a difference, but the setup I'm testing with is: a pinned Gmail tab in the default container, next to another pinned Gmail tab in a non-default container.

I'm using Firefox Developer Edition 83.0b10 if it helps.