--- a/calendar/chrome/calendar/calendar.properties
+++ b/calendar/chrome/calendar/calendar.properties
@@ -1,19 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
-# Misc. strings in JS
-
-# LOCALIZATION NOTE (PrintPreviewWindowTitle):
-#    %1$S will be replaced with the title of a html frame
-PrintPreviewWindowTitle=Print Preview of %1$S
-Untitled=Untitled
-
 # Default name for new events
 newEvent=New Event
 
 # Titles for the event/task dialog
 newEventDialog=New Event
 editEventDialog=Edit Event
 newTaskDialog=New Task
 editTaskDialog=Edit Task
@@ -185,97 +178,26 @@ tooltipOrganizer=Organiser:
 # task/todo fields
 # start date time, due date time, task priority number, completed date time
 tooltipStart=Start:
 tooltipDue=Due:
 tooltipPriority=Priority:
 tooltipPercent=% Complete:
 tooltipCompleted=Completed:
 
-# Tooltips for attendees and organizer in event and summary dialog
-
-# LOCALIZATION_NOTE(dialog.tooltip.attendee.combined): tooltip for itip icon in summary/event dialog.
-# Given an attendee loungeexample.org of type room is a mandatory participant and has accepted the
-# invitation, the tooltip would be:
-# lounge@example.org (room) is a required participant. lounge@example.org has confirmed attendance.
-# %1$S - value of dialog.tooltip.attendeeRole2.*
-# %2$S - value of dialog.tooltip.attendeePartStat2.*
-dialog.tooltip.attendee.combined=%1$S %2$S
-
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeRole2.CHAIR): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - value of dialog.tooltip.attendeeUserType2.*
-dialog.tooltip.attendeeRole2.CHAIR=%1$S chairs the event.
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeRole2.NON-PARTICIPANT): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - value of dialog.tooltip.attendeeUserType2.*
-dialog.tooltip.attendeeRole2.NON-PARTICIPANT=%1$S is a non-participant.
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeRole2.OPT-PARTICIPANT): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - value of dialog.tooltip.attendeeUserType2.*
-dialog.tooltip.attendeeRole2.OPT-PARTICIPANT=%1$S is an optional participant.
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeRole2.REQ-PARTICIPANT): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - value of dialog.tooltip.attendeeUserType2.*
-dialog.tooltip.attendeeRole2.REQ-PARTICIPANT=%1$S is a required participant.
-
-# LOCALIZATION_NOTE(dialog.tooltip.attendeePartStat2.ACCEPTED): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - common name or email address of the attendee
-dialog.tooltip.attendeePartStat2.ACCEPTED=%1$S has confirmed attendance.
-# LOCALIZATION_NOTE(dialog.tooltip.attendeePartStat2.DECLINED): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - common name or email address of the attendee
-dialog.tooltip.attendeePartStat2.DECLINED=%1$S has declined attendance.
-# LOCALIZATION_NOTE(dialog.tooltip.attendeePartStat2.DELEGATED): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - common name or email address of the attendee
-dialog.tooltip.attendeePartStat2.DELEGATED=%1$S has delegated attendance.
-# LOCALIZATION_NOTE(dialog.tooltip.attendeePartStat2.NEEDS-ACTION): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - common name or email address of the attendee
-dialog.tooltip.attendeePartStat2.NEEDS-ACTION=%1$S still needs to reply.
-# LOCALIZATION_NOTE(dialog.tooltip.attendeePartStat2.TENTATIVE): used to compose
-# dialog.tooltip.attendee.combined
-# %1$S - common name or email address of the attendee
-dialog.tooltip.attendeePartStat2.TENTATIVE=%1$S has confirmed attendance tentatively.
-
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeUserType2.INDIVIDUAL): used to compose
-# dialog.tooltip.attendeeRole2.*
-# %1$S - email address or common name <email address> representing individual attendee
-dialog.tooltip.attendeeUserType2.INDIVIDUAL=%1$S
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeUserType2.GROUP): used to compose
-# dialog.tooltip.attendeeRole2.*
-# %1$S - email address or common name <email address> representing a group (e.g. a distribution list)
-dialog.tooltip.attendeeUserType2.GROUP=%1$S (group)
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeUserType2.RESOURCE): used to compose
-# dialog.tooltip.attendeeRole2.*
-# %1$S - email address or common name <email address> representing a resource (e.g. projector)
-dialog.tooltip.attendeeUserType2.RESOURCE=%1$S (resource)
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeUserType2.ROOM): used to compose
-# dialog.tooltip.attendeeRole2.*
-# %1$S - email address or common name <email address> representing a room
-dialog.tooltip.attendeeUserType2.ROOM=%1$S (room)
-# LOCALIZATION_NOTE(dialog.tooltip.attendeeUserType2.UNKNOWN): used to compose
-# dialog.tooltip.attendeeRole2.*
-# %1$S - email address or common name <email address> representing an attendee of unknown type
-dialog.tooltip.attendeeUserType2.UNKNOWN=%1$S
-
 #File commands and dialogs
 New=New
 Open=Open
 filepickerTitleImport=Import
 filepickerTitleExport=Export
 
 # Filters for export/import/open file picker.  %1$S will be replaced with
 # wildmat used to filter files by extension, such as (*.html; *.htm).
 filterIcs=iCalendar (%1$S)
-filterXml=XML Document (%1$S)
 filterHtml=Web Page (%1$S)
-filterOutlookCsv=Outlook Comma Separated Values (%1$S)
 
 # Remote calendar errors
 genericErrorTitle=An error has occurred
 httpPutError=Publishing the calendar file failed.\nStatus code: %1$S: %2$S
 otherPutError=Publishing the calendar file failed.\nStatus code: 0x%1$S
 
 # LOCALIZATION NOTE (readOnlyMode):
 # used for an message like 'There has been an error reading data for calendar: Home. It has been...'
@@ -404,26 +326,21 @@ TZAlmostMatchesOSDifferAtMostAWeek=This 
 TZSeemsToMatchOS=This ZoneInfo timezone seems to match the operating system timezone this year.
 
 # LOCALIZATION NOTE (TZFromOS):
 # used for a display of a chosen timezone
 #    %1$S will be replaced with the name of a timezone
 TZFromOS=This ZoneInfo timezone was chosen based on the operating system timezone\nidentifier "%1$S".
 
 # Localization note (TZFromLocale): Substitute name of your locale language.
-TZFromLocale=This ZoneInfo timezone was chosen based on matching the operating system\ntimezone with probable timezones for internet users using UK English.
+TZFromLocale=This ZoneInfo timezone was chosen based on matching the operating system\ntimezone with likely timezones for internet users using US English.
 
 TZFromKnownTimezones=This ZoneInfo timezone was chosen based on matching the operating system\ntimezone with known timezones in alphabetical order of timezone id.
 
 # Print Layout
-formatListName = List
-weekPrinterName = Weekly Planner
-monthPrinterName = Monthly Grid
-
-# Print Layout
 tasksWithNoDueDate = Tasks with no due date
 
 # Providers
 caldavName=CalDAV
 compositeName=Composite
 icsName=iCalendar (ICS)
 memoryName=Temporary (memory)
 storageName=Local (SQLite)
@@ -574,29 +491,16 @@ severalLongCalendarWeeks=Calendar Weeks 
 singleShortCalendarWeek=CW: %1$S
 
 # LOCALIZATION NOTE (severalShortCalendarWeeks):
 # used for display of calendar weeks in short form like 'CWs 43 - 45'
 #    %1$S will be replaced with the index of the start-week
 #    %2$S will be replaced with the index of the end-week
 severalShortCalendarWeeks=CWs: %1$S-%2$S
 
-# LOCALIZATION NOTE (abbreviationOfWeek):
-# Used for displaying the week number in the first day box of every week
-# in multiweek and month views.
-# It allows to localize the label with the week number in case your locale
-# requires it.
-# Take into account that this label is placed in the same room of the day label
-# inside the day boxes, exactly on left side, hence a possible string shouldn't
-# be too long otherwise it will create confusion between the week number and
-# the day number other than a possible crop when the window is resized.
-#
-#    %1$S is a number from 1 to 53 that represents the week number.
-abbreviationOfWeek=%1$S
-
 # LOCALIZATION NOTE (multiweekViewWeek):
 # Used for displaying the week number in the first day box of every week
 # in multiweek and month views.
 # It allows to localize the label with the week number in case your locale
 # requires it.
 # Take into account that this label is placed in the same room of the day label
 # inside the day boxes, exactly on left side, hence a possible string shouldn't
 # be too long otherwise it will create confusion between the week number and
@@ -741,23 +645,20 @@ datetimeIntervalTaskWithoutStartDate=due
 # LOCALIZATION NOTE (dragLabelTasksWithOnlyEntryDate
 #                    dragLabelTasksWithOnlyDueDate)
 # Labels that appear while dragging a task with only
 # entry date OR due date
 dragLabelTasksWithOnlyEntryDate=Starting time
 dragLabelTasksWithOnlyDueDate=Due at
 
 deleteTaskLabel=Delete Task
-deleteTaskMessage=Do you really want to delete this Task?
 deleteTaskAccesskey=l
 deleteItemLabel=Delete
-deleteItemMessage=Do you really want to delete this Item?
 deleteItemAccesskey=l
 deleteEventLabel=Delete Event
-deleteEventMessage=Do you really want to delete this Event?
 deleteEventAccesskey=l
 
 calendarPropertiesEveryMinute=Every minute;Every #1 minutes
 
 # LOCALIZATION NOTE (extractUsing)
 # Used in message header
 #    %1$S will be replaced with language name from languageNames.properties
 extractUsing=Using %1$S
@@ -786,24 +687,10 @@ showOnlyCalendar=Show Only %1$S
 
 # LOCALIZATION NOTE (modifyConflict)
 # Used by the event dialog to resolve item modification conflicts.
 modifyConflictPromptTitle=Item Modification Conflict
 modifyConflictPromptMessage=The item being edited in the dialog has been modified since it was opened.
 modifyConflictPromptButton1=Overwrite the other changes
 modifyConflictPromptButton2=Discard these changes
 
-# LOCALIZATION_NOTE(dialog.attendee.append.delegatedFrom): this is appended behind an attendee name
-# in the tooltip and the visible name for an attendee in the event summary dialog - don't add
-# leading or trailing whitespaces here
-# %1$S - a single delegatee or a comma separated list of delegatees
-# delegation is different from simple invitation forwarding - in case of delegation the original
-# invited attendee gets replaced
-dialog.attendee.append.delegatedFrom=(delegated from %1$S)
-# LOCALIZATION_NOTE(dialog.attendee.append.delegatedTo): this is appended behind an attendee name
-# in the tooltip for an attendee in the event summary dialog - don't add leading or trailing
-# whitespaces here
-# delegation is different from simple invitation forwarding - in case of delegation the original
-# invited attendee gets replaced
-dialog.attendee.append.delegatedTo=(delegated to %1$S)
-
 # Accessible description of a grid calendar with no selected date
 minimonthNoSelectedDate=No date selected