Falkon can't open this URL https://build.neon.kde.org/view/2%20unstable%20%E2%98%A3%20git%20master/job/xenial_unstable_neon-packaging_calamares/ because it has a funky unicode character in it. Instead it sends it to the search engine.
Clicking on the link is fine, but copy the URL and open it in a new tab isn't happy
As a workaround, you can use "Shift+Enter" to force loading any url (even invalid) you type in locationbar.
Actually, it's the %20 that is the cause. *** This bug has been marked as a duplicate of bug 392445 ***