Don't want to sound harsh, but the absence of a keyboard shortcut renders it useless.
Just count the steps you have to follow in order to load a URL.
Assuming you have already copied the link you must:
1. Move the cursor on one of the bars/tabs
2. Right click
3. Scroll down and pick it
4. Click again
Now if you would please indulge me and compare it with the -no longer supported- “Paste and Go 3” [https://addons.mozilla.org/en-US/firefox/addon/paste-and-go-3/]
*Your custom keyboard shortcut* [e.g Ctrl+Shift+v] = > Paste & Go - ONE STEP!
*Your custom keyboard shortcut* [e.g Ctrl+Shift+s] = > Paste & Search - ONE STEP!
When it comes to convenience, there is NO comparison as to which is better.
Unless of course you're one of those types who, in order to save a file, would rather move the mouse to File tab and pick Save instead of merely pressing Ctrl+S.
Until someone manages to create such an add-on, I'm sticking with the *modified* version of “Paste and Go 3 1.0.5”
Zulkarnain K., your efforts and time you've spent developing this plug-in are greatly appreciated, that goes without saying.
BUT, there's always room for improvement - Can/Will you add customizable keyboard shortcuts?