Thanks to you for giving the extension a try! This is a very interesting feature, and I'd like to consider it. Would you mind filing an issue in the repo so we could track and discuss it here [1]?
+1. This was the first thing I tried to do and was surprised this feature doesn't exist. Most often, I don't encounter entire webpages in foreign languages, but rather small snippets of text.
Are you planning on adding a “select some text → right click → Translate in a tooltip” feature? It'd be extremely useful for language learners.