I’m using Firefox 41.0 (in Ubuntu 14.04). Steps to reproduce:

1. Go to Firefox privacy settings, set ”Remember history” (allow FF to restart if needed)
2. Install jump to anchor
3. Verify it works (context menu has ”Jump to anchor”)
4. Go to Firefox privacy settings, set ”Never remember history” and allow FF to restart
5. Open context menu

What happens:
”Jump to anchor” is missing from the context menu.