User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:80.0) Gecko/20100101 Firefox/80.0

Steps to reproduce:

1. Start firefox with a new clean profile.
2. Install "Firefox Multi-Account Containers".
3. Go to https://en.wikipedia.org/wiki/Jack_Dorsey#External_links (you can do that from a "No Container" tab, it doesn't matter).
4. Right click on the link to Dorsey's twitter profile and select "Open Link in New Container Tab -> Personal".
5. The twitter page tab now runs in the "Personal" container. Close that tab.
6. Press Ctrl+Shift+T to reopen the last closed tab.
7. Notice that the reopened tab runs in "No Container" mode.

Actual results:

The restored tab should run in the "Personal" container.

Expected results:

By closing and reopening the tab the container changed from "Personal" to "No Container". Note that while I suspect that this can happen with other sites, I was only able to reproduce 100% reliably for pages in twitter.com.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

I can reproduce the issue on Nightly82.0a1 with new profile Windows10 without the addon.

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=8fe4738543cbff085e7d43da5ece4c80f4181291&tochange=f8343d64ab6f3a66fbc7d47484758725cb0335c2

browser.tabs.remote.useCrossOriginOpenerPolicy = false fixes the issue.

Thanks for reporting! Looks like a dup of Bug 1665942?

I believe that's a dup of Bug 1665942 and am going to close this one

Bug 1594748 only changes the default value for prefs on release and late beta so I wouldn't say it's regressed by bug 1594748. It's probably regressed by some other ticket that implemented the feature.