How do you open a PDF in a new tab and show it in the browser (don't ask to download)?

Question

I have a link to a PDF and when I click on it I want it to open a new tab and render in the new tab as opposed to asking me to download it. How do I do that?

note, I'm asking this question so I can answer it. This information can be pieced together from other answers, but I'd like it to be all in one place

Solution

To open a link in a new tab (PDF or not) you must modify the HTML of that link from

<a href="/link_to_pdf.pdf">PDF</a>

to

<a href="/link_to_pdf.pdf" target="_blank">PDF</a>

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To open a PDF in the browser you must make a server side change to the response header. In Java, you would do this:

response.setContentType("application/pdf");
response.addHeader("content-disposition", "inline; filename=link_to_pdf.pdf");

Of key importance is the inline. If you put attachment, your browser will try to download it instead. You can read more here.