Use a more convenient command. Caveats: malicious urls containting
`'$(rm -rf ~/)'` (note the use of single quotes) or similar will be executed.
Single quoting will protect from most attacks such as `$(rm -rf ~/)`.
Use the following if you want to validate the command before running:
`CommandExMode().open("!quvi '" + loc + "' &> /dev/null &")` or
`io.system("quvi " + io.shellEscape(loc) + " &> /dev/null &")`