I don't always upload images from the clipboard. But I do sometimes and when I was using Chrome it was a pain. But Opera's that little popup window that pops whenever I click on an upload button is very useful when I want to upload from the clipboard. But, Whenever I want to upload something from the Browse files I essentially have to click twice to get the file browser (One for the upload button and the second for the "Show all files" for the popup feature) and I think it would be better to use something like the key combination to upload from the clipboard.
Here's an example
Normal Click (LMB) on the Upload button - Directly pops up the File browser to choose a file (not showing the upload feature at all.)
Ctrl + LMB on the Upload button - Directly pops up the Upload from the clipboard to choose a file from the clipboard.
Reason was that I use both of these cases usually and It is a pain to upload images from the file browser since I have to click on two buttons to upload from the file browser. In that case, the pop feature is really annoying. But I don't want to disable it because I upload from the clipboard too (usually).