pdf unreadable: reports password protected when it's not.
Regarding the attached file:
I am able to read in Brave's pdf plugin and also in MuPDF. On the other hand, when I try to open with evince v.3.18.2 (or qpdf or calibre), I am asked for a password.
(Sorry, it's a little big.)_2.2__Our_Changing_Climate.pdf