I signed up specifically to ask this question, because this website is one of the only places I have found this extra line of text in the warlock's "Eyes of the Rune Keeper" eldritch invocation from D&D 5e.
On a few posts here, I have seen Eyes of the Rune Keeper quoted as:
You can read all writing. You can comprehend any written word or symbol, should it hold any linguistic meaning
I haven't been able to find this specific description for the invocation in any official documentation; I've looked through the PHB, both versions of the released errata for the PHB, XGE (most of the official reference books), scoured through Sage Advice, and I can only find one other non-official reference to the extra line of text over at the DND5E Fandom wiki.
Is there any official reference document that contains the second sentence in the above quote? Or is the following sentence the only official description of the ability?
You can read all writing.