In every program, if you hover over a button, and start holding the left click button, than unhover on it, and stop holding the left click button, it won't click the button.

In Minecraft however, it does not check, if on releasing the left click button was the cursor on the button, but instead instantly on clicking the left click button, not even at releasing it, it checks if it's on the button, and if it is, it instantly performs the button's action.

This might not seem like a huge issue, but infact it is, as it is very annoying for some people. Please don't tag it saying "Not a bug", "Invalid" or "Won't fix" as it is a very important issue.