There are multiple 30th dates shown. I have tested in current chrome version:
Version 61.0.3163.100 (Official Build) (64-bit)
And also in
Version 62.0.3202.38 (Official Build) beta (64-bit)
OS is Win10.
My timezone is (UTC +01:00) Brussels, Copenhagen, Madrid, Paris
Daylight Saving Time began on Sunday, March 26, 2017 at 2.00
Daylight Saving Time ends on Sunday, October 29, 2017 at 3:00.
Daylight Saving Time begins on Sunday, March 25, 2018 at 2:00.
And also this person got issues:
Daylight saving time 2017 in California began at 2:00 AM on Sunday, March 12
and ends at 2:00 AM on Sunday, November 5
All times are in Pacific Time.