I notice that the languages in the drop down list are all in English (default). When the language is changed to another language, then the list of languages is changed so all the list is in the new language.
This is good for the situation where the person using the site wants to see what it looks like in another language to their own. But it can make rather difficult to read your own language from the list when it is in another language.
It would be helpful to have the option to have each language in the drop down list, displayed using its own native name and characters for itself. This way each visitor to the site can at least recognise and find their own language from the list, and then select.
This benefit is naturally available when the flag display is used, but only if the respective flag is enabled for display. The drop down list, lists all the languages, but not all flags are necessarily displayed. So the drop down list ensures that all languages are available for translation, even if it is difficult for a user to choose their own language when the list is displayed in a foreign language.
It would be handy to have the admin option to let the site visitor have the rest of the un-displayed flags be displayed either by hovering over the flag list, or by clicking a button (that could be the last icon in the flag display, say with a down arrow).