This Behaviour helps to view time/date/timestamp/datetime from db to local Date / Time / Date Time format and in local Timezone. And save into db in with db timezone and db format. You only need to include this behaviour in models where need this facility.
With the adoption of PJax on Yii2 things have change quite a bit with GridView when it comes to work with them in AJAX mode. It will probably be confusing at the beginning, but then you will soon realize how powerful the new approach is.
I wanted to keep all the I18N related translations in separate files, so that I would not need to modify the view files or the model files every time I need to update or fix the translations
of application's source language.
You have that, when a product is on development they can change its API anytime. This change is quite important though, its related on how to set the events of your form, for example, the useful beforeSubmit.
The CGridView widget is very useful and customizable, but sometimes you need a little more.
One limit I found is to have only one row for headers; yes, you can write each column header in more than one row, but just inside the single cell.
I was looking instead for the possibility to use more than one row, with different structure one from the others.
This way you can write columns grouping headers, and obtain a nicer view.