I`ve just tried it (on an Ainsley Harriott Caribbean cookery programme) and there is a large 'S' next to the full screen symbol on the bottom right of the screen (not top right as the link says)
Are you using a "connected tv with a wireless hub?
If so the ITV help pages say "We do offer subtitles on most of our shows on the website but unfortunately we don’t have them available on Connected TVs. We are looking to introduce subtitles across all devices very soon."
I am trying to get them on Manhunt and use Wi-Fi I think. I cannot be sure but am certain I have had them on ITV in the past on THE hUB. Get them no trouble on BBC.
Have tried everything my tired 80+ brain can muster but still no joy. We manages to watch the first 2 episodes on recorder but the final episode failed to record and as all the final one contains all the nuts and bolts need good ears which I haven't to get the facts and understand the rest.
Yes got it on the computer OK with Subtitlesbut is quiye a small screen. Still got 14 days to watch it so might be lucky on th TV before then, here's hoping.