Recently, I got an for improvement which you might find useful:

The green toolbar above enables you to enter a target language (left dropdown) and your native language (right dropdown). I often mix german/english up as it speeds up the comprehension of text. It's easier to translate an unknown word into a second language than look it up in a dictionary.

It would be awesome if you could add a button to fast switch between the two selected languages.

English to German <-> German to English.

I often read articles in both languages and the fast switch would make the experience more fluent as you don't have to browse through the long dropdown menu to find the same languages but in reversed order.

Cheers.