[malf]

I thought the days of “opening a pdf freezes IE for several seconds” were long past. What makes this painful for you?

[withinboredom]

Whether or not to open on a mobile device? I usually don't open PDFs on a mobile because it is a pain to read.

[detrites]

PDF's also present privacy and security risks (the question's old but answers been updated):

https://security.stackexchange.com/questions/72037/what-are-...

[quickthrower2]

Many HTMLs have the same issue

[withinboredom]

“Reading mode” usually solves this with HTML

[TheRealPomax]

Who said anything about painful? HN posts that are direct downloads for pdf files are universally marked with [pdf]. Either because the poster remembered to do so, or because the title gets edited after the fact.

This is not an article, it's a download, and should be marked as such.

[yencabulator]

It's only a download if your browser chooses not to display it. On Chrome, it's just another tab among tabs; you can choose to save to a file if you want.