In plugin-cms/resources/js/tinymce/styles.js file, label for styles are added using `editor.ui.registry.addIcon` method. Other methods should probably be used, such as `addMenuItem`
Currently, this lead to bugs, in particular the fact that the label has a width of 150px despite the whole dropdown is smaller than that. As the structure of display flex is here to handle icons and not text, the dropdown is also not resized according to the length of the label.