Before the new UI it was possible to paste an image into the assistant and have it react to it. This feature no longer works.
To replicate, open a new Thread in the Assistant, copy an image into clipboard, focus the Thread and press "CTRL+V". Nothing happens.
I expect to be able to paste an image from the clipboard and make it available to the Assistant.
I used this a lot by screenshot-ing a part of my screen into the clipboard and then pasting it into the Assistant. Having to save each screenshot into a file in order to upload it into the Assistant is so cumbersome I don't bother anymore, and I notice that it's reduced the value I get out of the Assistant considerably.