Steps to Reproduce: 1) Install Multi-Account Containers add-on 2) Create several different containers 3) Open tabs in each of the different containers 4) Restart Firefox by going to about:profiles and clicking "Restart normally" Observed behavior: Tabs are not restored to any container upon restart. Expected behavior: Tabs are restored to the containers with which they were opened. Other remarks: This poses a security and privacy risk, as information leakage occurs when previously segregated websites are loaded outside of their containers all at once.