These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Withnail and I
"Funny Aneurysm" Moment: Withnail is shown drinking lighter fluid, to Marwood's dismay. The real-life person he was based on died of throat cancer (nearly ten years after the movie came out), which the scriptwriter, who based Marwood on himself, blamed on the time he actually did drink lighter fluid.
Harsher in Hindsight: Withnail was originally to be depicted committing suicide at the end. Vivian MacKerrell, on whom he was based, died at only 50, due to throat cancer most likely caused by self-destructive behavior of some sort.
Made canon by Withnail getting "carried away" when he told Monty that Marwood was a "toilet trader" who was in love with him.
See also: Marwood's constant violation of Withnail's personal space, the tendency for the two of them to call one another "lovey", and Withnail's insistence, in the interest of their "safety", that they share a bed.
Incidentally, Danny remarks that Marwood is "looking very beautiful" when he sees him emerging half-dressed from the bathroom.