This is the workaround I did>>>
BELOW WAS FOR ADOBE VERSION 9.1.3
I also Disabled "Enable Java Script" by unchecking this box too,
Disable the display of PDF documents in the Web browser
Preventing PDF documents from opening inside a Web browser will
partially mitigate this vulnerability. If this workaround is
applied it may also mitigate future vulnerabilities.
To prevent PDF documents from automatically being opened in a Web
browser, do the following:
1. Open Adobe Acrobat Reader.
2. Open the Edit menu.
3. Choose the preferences option.
4. Choose the Internet section.
5. Un-check the "Display PDF in browser" check box.
Do not access PDF documents from untrusted sources Do not open unfamiliar or unexpected PDF documents, particularly
those hosted on Web sites or delivered as email attachments. Please
see Cyber Security Tip ST04-010.
So I guess you are saying the workaround is no longer needed, I dont see anything on the website you supplied about version 9.20?
Is this correct?