I'm submitting a tab but I don't get the blue letters when I preview it? Is this supposed to happen? Like will it do it automatically or do I have to code it into the tab.
It'll do it automatically once it's made available on the site.
Just select 'chords' as type of your tab.
The 'blue chord' is the holy grail of many guitarists. It can only be achieved after a lifetime of manual labour and months (preferably years) spent homeless underneath bridges drinking whiskey. Once achieved it will bring upon the guitarist great fame and success. cf. Robert Johnson, Muddy Waters, BB King