Hostnames which have unpunycoded IDN or canonical
name information will have this information reported
as an extra line under the hostname name in the popup
panel, rather than as a tooltip.
For the fenix UI flavor, the save/revert tools are
now shown regardless of whether the overview area is
visible or not.
First draft of changes as discussed with Firefox
Preview people.
In order to allow testing/evaluating these changes,
the new advanced setting `uiFlavor` has been added.
Default to `unset`; and can currently only be set
to `fenix`.
The new setting takes effect at launch only. This
new setting is not to be mentioned in official
documentation for now.
This is ongoing work, not open to external feedback.
