This also introduces a combo grid/flex layout, which will also be
applied to the DM and Streams headings.
Because there are now multiple classes referenced from the
Puppeteer tests, those selectors now include the expanded
navigation area's parent ID selector.
Previously this dropdown was only for selecting streams, but
soon it will also be for switching to a private message. This
name helps it be clearer that the dropdown is more general
purpose.
Fixes#11832
This lets the user see more options than the three that appear
in the typeahead menu, and prevents them from inputting invalid
stream names.
This change replaces the input field with the dropdown, and
updates everything that referred to the classnames of the old
input field, so that they now get the data they need from the
new dropdown.
Updates frontend user-facing strings with "private message" or "PM" to
use "direct message" or "DM" respectively instead.
Note that this updates translated strings as well as a few that
are not translated like search suggestions.
Updates `tools/lib/capitalization.py` for some specific strings
that are impacted by these changes, and removes "PM" and "PMs"
from checked strings.
Aman Agrawal
Anders Kaseorg
Karl Stolley
evykassirer
Lauryn Menard
Hardik Dharmani
evykassirer