Hello Christian Phan,

If you need to know the exact time for certain purposes, you can hover over the relative timestamps (like "2 minutes ago" or "14 days ago") to see the precise date and time of the message, as shown in the image.

Currently, there is no setting available to change this format directly. Customization on the code side would be necessary to implement your desired changes. Alternatively, you could also check the Odoo App Store for any modules that might provide this functionality.

Hope this Helps,

If you need any help in customization feel free to contact us.

Thanks & Regards,

Email:  odoo@aktivsoftware.com           

Skype: kalpeshmaheshwari