Think it’s the standard SafariKit SDK (as opposed to the WebKit one you can completely control)…
For OneSub, Charlie et al, Apple force us to use this one … but presumably Twitter just chose this for usability.
Maybe other workground but the current „Translate“ option opens in external safari as well. The inline translation in X is much sexier. I don’t think that it is big one to have a div in any item which can silently filled by result of google translation api 😃
Have it installed and indeed the embedded browser and translation is perfect. Threads are displayed as single messages in Timeline that’s bad. I also miss the moderation menu where blocklists can be managed. A mixture of both clients would be perfect 😅