Investigation: Why are some old Comment is Free liveblogs rendering incorrectly in DCAR?

[SiAdcock]

From CP:

Was looking at this old community project from 2017 https://www.theguardian.com/commentisfree/live/2017/mar/03/what-even-is-a-hipster-join-our-live-look-at-the-week-to-discuss-this-and-more

and it should look more like this

https://www.theguardian.com/commentisfree/live/2017/mar/03/what-even-is-a-hipster-join-our-live-look-at-the-week-to-discuss-this-and-more?dcr=false

Another from the same series, here should look more like this

But some of them, eg here, are fine ...

Do you know what's happened and if this might be a wider issue with older liveblogs?

[SiAdcock]

Might be a clue in some of the embeds I wondered, in Composer I saw this where a tweet was placed: