TARDIS Wiki (in-universe)

The TARDIS Wiki, (PROSE: Lady Peinforte) stylised as Tardis | Fandom on Petronella Osgood's tab on Chrome, was a website, (WC: The Zygon Isolation) that Lady Peinforte described as a "place of secrets", and which she cribbed from to learn of the Doctor's secrets. (PROSE: Lady Peinforte)

History
After Lady Peinforte and Richard Maynarde travelled forwards in time to Windsor in 1988, she accessed, through unknown means, the TARDIS Wiki, where she learned of the question "Doctor who?" and how his name was "a promise he made to himself to not be cruel or cowardly". She claimed to know of his secrets; that of the Looms, though she deemed those non-canonical; the the Doctor being half-human on his mother's side, which she claimed was "much disregarded"; the Doctor's barn, his departure from Gallifrey in fear of the Hybrid, and Gallifey of the old time. (PROSE: Lady Peinforte)

The human Osgood had the website open in another Chrome tab while settling down to watch Doctor Who on iPlayer with her Zygon counterpart. It bore the heading of "Fandom". Its logo resembled the police box exterior of its timeship namesake. (WC: The Zygon Isolation)

Behind the scenes
Clearly, both stories are suggesting that this very wiki exists in the Doctor Who universe.

Unlike the real world Tardis Wiki, however, which has asserted since 2012 that there is no canon and instead follows rules for "validity" in determining coverage, TARDIS Wiki in the DWU not only makes decisions on canonicity, but has decided that Looms (and other elements introduced in Lungbarrow) are non-canonical.

In the real world, Lungbarrow is actually considered a valid source, and, in keeping with T:NPOV, is considered equally alongside "other accounts" for the Doctor's early life and Time Lord history generally.

This unique situationwas made more aware to the community when Twitter user going by the handle DrWhoMoment shared this Wiki page to his Twitter followers. https://twitter.com/DrWhoMoment