--- a/calendar/chrome/calendar/calendar-event-dialog.properties
+++ b/calendar/chrome/calendar/calendar-event-dialog.properties
@@ -130,16 +130,28 @@ monthlyRuleNthOfEveryNounclass1=%1$S сваког месеца;%1$S сваких #2 месеца
 # considered in 'repeatDetailsDayxNounclass' strings. For languages that need
 # localization according to genders or noun classes.
 # Nounclass1 <-> Masculine gender; Nounclass2 <-> Feminine gender.
 # Add 'repeatOrdinal...Nounclass' strings with suffix 3, 4 and so on for
 # languages with more than two noun classes for weekdays. In this case
 # must be added corresponding rule strings with 'Nounclass...' suffix and
 # corresponding values "nounclass..." must be written in
 # 'repeatDetailsDayxNounclass' strings.
+repeatOrdinal1Nounclass1=први
+repeatOrdinal2Nounclass1=други
+repeatOrdinal3Nounclass1=трећи
+repeatOrdinal4Nounclass1=четврти
+repeatOrdinal5Nounclass1=пети
+repeatOrdinal-1Nounclass1=последњи
+repeatOrdinal1Nounclass2=први
+repeatOrdinal2Nounclass2=други
+repeatOrdinal3Nounclass2=трећи
+repeatOrdinal4Nounclass2=четврти
+repeatOrdinal5Nounclass2=пети
+repeatOrdinal-1Nounclass2=последњи
 
 # LOCALIZATION NOTE (yearlyNthOn):
 # Edit recurrence window -> Recurrence pattern -> Yearly repeat rules
 # %1$S - month name
 # %2$S - day of month possibly followed by an ordinal symbol (depending on the string
 #           dayOrdinalSymbol in dateFormat.properties)
 # #3   - yearly interval
 # e.g. "every 3 years on December 14"

--- a/calendar/chrome/calendar/calendar.properties
+++ b/calendar/chrome/calendar/calendar.properties
@@ -448,43 +448,47 @@ daysIntervalBetweenMonths=%1$S %2$S – %3$S %4$S, %5$S
 #    %1$S will be replaced with name of the month of the start date
 #    %2$S will be replaced with the day-index of the start date possibly followed by an ordinal symbol
 #    %3$S will be replaced with the year of the start date
 #    %4$S will be replaced with name of the month of the end date
 #    %5$S will be replaced with the day-index of the end date possibly followed by an ordinal symbol
 #    %6$S will be replaced with the year of the end date
 # The presence of the ordinal symbol in the day-indexes depends on the string
 # dayOrdinalSymbol in dateFormat.properties
+daysIntervalBetweenYears=%1$S %2$S, %3$S – %4$S %5$S, %6$S
 
 # LOCALIZATION NOTE (daysIntervalBetweenYears.monthFormat):
 # If your language requires a different declension, change this to
 # one of the values specified in dateFormat.properties.
 # In any case, DO NOT TRANSLATE.
 
 # LOCALIZATION NOTE (datetimeIntervalOnSameDateTime):
 # used for intervals where end is equals to start
 # displayed form is '5 Jan 2006 13:00'
 #    %1$S will be replaced with the date of the start date
 #    %2$S will be replaced with the time of the start date
+datetimeIntervalOnSameDateTime=%1$S %2$S
 
 # LOCALIZATION NOTE (datetimeIntervalOnSameDay):
 # used for intervals where end is on the same day as start, so we can leave out the
 # end date but still include end time
 # displayed form is '5 Jan 2006 13:00 - 17:00'
 #    %1$S will be replaced with the date of the start date
 #    %2$S will be replaced with the time of the start date
 #    %3$S will be replaced with the time of the end date
+datetimeIntervalOnSameDay=%1$S %2$S – %3$S
 
 # LOCALIZATION NOTE (datetimeIntervalOnSeveralDays):
 # used for intervals spanning multiple days by including date and time
 # displayed form is '5 Jan 2006 13:00 - 7 Jan 2006 9:00'
 #    %1$S will be replaced with the date of the start date
 #    %2$S will be replaced with the time of the start date
 #    %3$S will be replaced with the date of the end date
 #    %4$S will be replaced with the time of the end date
+datetimeIntervalOnSeveralDays=%1$S %2$S – %3$S %4$S
 
 # LOCALIZATION NOTE (datetimeIntervalTaskWithoutDate):
 # used for task without start and due date
 # (showed only in exported calendar in Html format)
 # LOCALIZATION NOTE (datetimeIntervalTaskWithoutDueDate):
 # used for intervals in task with only start date
 # displayed form is 'start date 5 Jan 2006 13:00'
 # (showed only in exported calendar in Html format)

new file mode 100644
--- /dev/null
+++ b/calendar/chrome/calendar/timezones.properties
@@ -0,0 +1,39 @@
+# 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/.
+
+# extension:
+
+pref.timezone.UTC=UTC/GMT
+
+# I've derived this list out of timezones.dtd
+# - replaced '_' with ' ' on value side
+# - corrected 'St xyz' to 'St. xyz'
+
+# timezone names:
+
+# the following have been missing
+
+# added with 2008d:
+
+# added with 2008i:
+
+# added with 2010i
+
+#added with 2011b
+
+#added with 2011n
+
+#added with 2013a
+
+#added with 2014b
+
+#added with 2014j
+
+#added with 2.2015g
+
+#added with 2.2016b
+
+#added with 2.2016i
+
+#added with 2.2016j