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* Feat: the navbar has been removed and its content has been added in the sidebar that is fixed to the window.
* Feat: modal has been added to confirm the deletion of an object.
* Feat: templates and style have been changed.
* Feat: selection widgets have been incorporated.
* Feat: bulma's tags are used to display a field of multiple objects.
* Feat: the templates used in the tests have been updated.
* Feat: filters stick to the screen (if problems arise it could be removed).
* Feat: notifications can be removed.