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If you need displaying dates and times for some projects but dates only for other projects, the receipt above does not work as this is a global change effecting , which effects all projects within your JIRA.
Alternatively, just use the option "Running Gantt-Chart v3.2.3 or newer, you can use the alternative approach via look & feel option. Please open the related menu "Configure Look & Feel" on your Gantt-Chart:
Then select the first tab and check option "Display dates without time" on tab "Look and Feel Configuration" of the Gantt menu : this requires Gantt-Chart v.3.2.3 or newer.
. The preview within the same row on the right displays the result. Being ready, please click on button "finish" to store your choice.
Be aware, that this option is an individual setting per logged in user and selection (filter, agile board, structure).
Related articles
https://confluence.atlassian.com/display/JIRA061/Changing+Custom+Field+Types
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