Yes, I've had a number of 20 second waits over the last few days.

Noticed it's been struggling a bit the last two or three days.

It seems to be better now. I think they were training a new hamster.

What    is   a   PDF

Portable Document Format - a file which can contain rich text, images, all sorts of stuff. Popular in the days when people used various different word processor applications with differing formats.  Originally intended as a read-only format I think.   Usually formatted into pages as they would be printed.  So like a Word Processor document but can be read on different software platforms using a PDF reader and without needing to own MS Word, Office or whatever. 

The "Attachments and other options" function on here seems to be limited to PDFs, I guess it's to allow someone to attach documents, instruction sheets and other useful stuff like that.   

Unfortunately when newbies first want to add photos they notice the Attachments option, discover it only works for PDF and convert their photos to PDF files in order to upload something.

Same as Nick, it tends to rotate photos I post from my phone, but otherwise it works pretty faultlessly.