All current Firefox versions, Windows 8.1

A '% <searchterm>' search in the addressbar doesn't find anything if the current and the open tab (for which the search matches) are in different container environments (including the default one).

Steps to reproduce:

If the product is not Nightly:

1. Open about:config from the addressbar.
2. Confirm the warning.
3. Set privacy.userContext.enabled to true.
4. Set privacy.userContext.ui.enabled to true.
5. Set privacy.userContext.longPressBehavior to 1.

For all builds:

1. Launch a profile.
2. Open a web page in the open tab, e.g. https://en.wikipedia.org/wiki/Central_European_Midsummer_Time
3. Click the '+' button in the tab bar.
4. Open a tab in a tab environment from the menu which opened.
5. Type summer in the url bar of the new tab.

Actual and expect result: https://en.wikipedia.org/wiki/Central_European_Midsummer_Time suggested
Actual result: Open tab not suggested.
Expected result: Open tab suggested.

6. Delete the content of the address bar.
7. Type % summer instead.

Actual result: Open tab not found.
Expected result: Open tab found.