The Wikidata dialogs and the create/import project panels append (:) to the labels which are not consistent with the rest of the application.
In general for web applications, colons are no longer used in modern web design.
Don’t add a colon (:) at the end of a field label to imply that the label text applies to the field it accompanies. The design of the component already communicates the relationship between the label and the input field.
Reference: https://spectrum.adobe.com/page/field-label/
The Wikidata dialogs and the create/import project panels append (:) to the labels which are not consistent with the rest of the application.
In general for web applications, colons are no longer used in modern web design.