I'm using Iceweasel/release on Debian/Jessie and had the same error after
the last Iceweasel upgrade (40.0.3-3 => 41.0-1).
In fact, NoScript was reported as "not compatible with v41" in
about:addons and I could not even re-enable it after I disabled it
temporarily to try to get the menu back again.
However, I think it may be too much work to maintain different versions of
every Mozilla addon for every flavour of Iceweasel versions (esr,
release, beta, aurora, testing, etc...).
For now I've switched to the upstream version of NoScript and the menu is back.
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