I could be wrong but it looks like the datetime-picker from angular does not work with angular 16, even though it claims it does. I took the demo from the NPM page for the package, updated the package.json, and then all of the styling of the picker broke. This was the case when I tried to upgrade my own application too. Does anyone know if there is a new dependency that is not mentioned anywhere or a change to the way it's used or something?
Here is the Stackblitz, just make sure to press the update dependencies button to have it load in the angular 16 ones. Press the calendar to see the broken formatting.
https://stackblitz.com/edit/demo-ngx-mat-datetime-picker-vrtdak?file=package.json
The problem seems to be in Angular 16.2.1, when I downgraded to Angular 16.1.1 it worked. Not sure why but that is for someone else to figure out sometime I guess. If you are using the datetime-picker just downgrade.