My prior systems were mostly WinXP, with one Win7, and they are all up and running, so I can compare the behaviour of NS.
The brand new machine (less than 2 weeks), where the problem occurs, came with Win10, but I suspect that the problem lies in the version of NS (2.9.0.11) or some other addon, rather than in the version of Windows.
The symptom: The context menu of NS contains almost nothing. “Options” is always there, but there is usually only one other command, depending on the page that is loaded on that tab. Most often, it's “Blocked objects” that is available and that one sometimes allows me to workaround the bug by using one of its “Temporarily allow...” commands.
At first I suspected interference with some other addon (I installed the same 10 addons as on all my other systems, with the same settings for each one), so I deactivated all those that can be deactivated: no difference. Then I proceeded to uninstall them all, one by one, testing NS after each uninstallation (including restart when required). After uninstalling the last one, the symptom was still present.
So I started from scratch with a new Fx profile and tested NS after the installation of each separate addon. This time, it looked like the symptom was gone for good because NS was still normal even after installing the 10th addon. (That is Tab Mix Plus, which doesn't require a restart.) But later I had to restart Fx for some other reason and now the symptom is back!
After each restart, it looks like the content of the NS context menu is fine (on an empty tab, it offers “Allow about:newtab”, “Temporarily allow about:newtab”, etc.), but as soon as I open some Web page, the NS menu gets stripped down to 2 commands.
For example: windowsreport.com
Right now, on this machine, the NS menu only shows:
- “Blocked objects”
“Revoke temporary permissions”
“Options”.
- 5 pairs of “Allow...” and “Temporarily allow... ” for sites such as windowsreport.com and www.google.com
“Blocked objects”
“Untrusted”
“Temporarily allow all this page”
“Options”