I open PDF files in Firefox, and notice that content scripts from my extensions aren’t executed (it’s on other pages, and I’ve “<all_urls>” in the manifest). For example, I just placed a console.log print inside one, and the line is never printed. I recall that PDF pages did use to run content scripts a while ago, until it suddenly stopped with a certain release (but I don’t remember which one).
Is this a recent change? Is anything else expected to be done for PDF pages?