They have not deprecated the attribute "uib-datepicker-popup", the warning is related to all attributes listed in datepicker docs in section "Datepicker Settings". You have to provide those values by the attribute "datepicker-options".
Don't know why but those in section "Popup Settings" are not throwing the warning.
In my case I had
JS
$scope.datepicker.format = "shortDate";
$scope.datepicker.options = {
formatYear: "yy",
startingDay: 1,
};
HTML
<input type="text" class="form-control"
ng-model="ngModel"
uib-datepicker-popup="{{ datepicker.format }}"
datepicker-options="datepicker.options"
datepicker-append-to-body="true"
is-open="datepicker.opened"
show-button-bar="false"
close-text="Close"
min-date="minDate"
max-date="maxDate"
custom-class="getCustomClass"
show-weeks="false"
/>
and it became
JS
$scope.datepicker.format = 'shortDate';
$scope.datepicker.options = {
formatYear: 'yy',
startingDay: 1,
minDate: minDate,
maxDate: maxDate,
showWeeks: false,
customClass: getCustomClass
};
HTML
<input type="text" class="form-control"
ng-model="ngModel"
uib-datepicker-popup="{{ datepicker.format }}"
datepicker-options="datepicker.options"
datepicker-append-to-body="true"
is-open="datepicker.opened"
show-button-bar="false"
close-text="Close"
/>
Update
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plunker reproduction