Users might want to filter incoming updates based on the file endings on top of/instead of the mime type. Both attributes of documents are not safe, but that didn't stop us from introducing a mime type want and shouldn't stop us from a file ending one either. Both are a great way of initially filtering incoming files. We should just mention in the docs, as we do with mime types, that telegram does

Please, make Chattable interface more friendly for the library clients:

// Chattable is any config type that can be sent.
type Chattable interface {
	Values() (url.Values, error)
	Method() string
}

Currently, Telegram bot has many methods that are not implemented in your library.

I try to switch from RamBox to Ferdi. However I have several services with the same icon (slack, nextcloud). It would be a great help if I just cloud add a small textual label next to, under, over the icon. Don't care where.

Sorry that this is not a pull request, my JS/css knowledge is insufficient. I tried copying the tooltip to a div. Didn't get the correct tooltip and a misplaced div...