When using JSON text, the "open_url" option for "clickEvent" does not do anything. I tested my configuration by changing
tellraw @a {"text":"help","clickEvent":{"action":"open_url","value":"www.google.com"}}
to
tellraw @a {"text":"help","clickEvent":{"action":"run_command","value":"www.google.com"}}
and running the command. Upon clicking the word "test" it outputs "www.google.com" to the chat as it should be, but the original configuration will do nothing when clicked.