As I wrote in post #7..
..after 5.1.5 was auto-updated into 5.1.7, I also got the "all white" NoScript issue,
and fixed it by manually installing 5.1.6 and turning off auto-updates.
Today, however, I read this..:
Guest wrote:I ended up getting 5.1.7 working..
..and so I wanted to try to get 5.1.7 working myself, too.
I used DTA to download and save the 5.1.7 xpi to my Downloads folder,
then restarted Firefox, and chose from the menu..
File ->
Open File... (Ctrl + O) -> "noscript-5.1.7.xpi"
and installed 5.1.7 that way.
My plan was then to delete the Profiles \ startupCache folder,
but I just figured that I would check to verify that NoScript had turned "all white" again..
..and it didn't! Everything was still OK. I restarted Firefox, still OK.
So that was unexpected.
Finally, just as an experiment, I re-installed 5.1.5 and let it auto-update into 5.1.7,
and 5.1.7 was OK this time also. Apparently something strange happened that first time.