This version is a pre-release. Read the release notes


In order to support the browsers that FullCalendar aims to support, we need to introduce that concept of a “time zone implementation”, a way to define which system is responsible for computing time zone offsets for arbitrary dates in arbitrary time zones.

The timeZoneImpl setting only comes into play when using named time zones for the timeZone settings. If you are using the 'local' or 'UTC' time zones, you do not need to worry about timeZoneImpl.

"UTC-coercion" is the default setting. This requires no third party plugins. It “coerces” or “forces” the dates that it receives into native Date objects whose UTC-values are relevant. You’ll need to remember to use methods like getUTCDate() and toUTCString() on these date objects.

When parsing ISO8601 strings that have UTC offsets, like 2019-09-01T12:30:00-05:00, the offset (-05:00) will essentially be ignored! For more information, visit the “UTC-coercion” section in the main timeZone doc.

If you’d like a more proper solution that represents dates in their true offsets, third-party plugins are available to you. Remember, these plugins require other date-libraries which will add bloat to your final bundle: