Why cant i view screenshots on threads?

Instead of right click on screenshot to view just left click and open in new link
 
But this is also failing as some time it says that the path is not valid or something like this.
Sorry mate thats all i tried i just left click on screenshot then at top of list just clicked open link and worked!
 
I know that thats the way, but why cant we use the old system no more?
 
I am now having to use the Control button and then clicking on image but it is really annoying when i forget to do that and it comes up a grey screen.
 
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