This problem maybe began with new 5.1.2 or with newest Firefox upgrade last fortnight . NoScript was present and busy blocking but not reachable through icon or low bar ( which i use every minute ) . Through the menu of Firefox i could read that my noscript settings were normal thus lying that reachable ¨show menu¨ , and i didn´t find much tool , maybe deleting and reinstalling .
So , I go to site noscript.net and reinstall . Every time i close down Firefox and restart Firefox and/or pc ( about every week , or 9 seconds ) , icon and bar are gone ( which the settings don´t admit ) . So i go to site noscript.net and reinstall again and again after closing ( throwing away every job on screen ) and starting Firefox . Even my usual settings survive. ( BTW Never choose setting to Forbid Every java , the icon and bar will disappear too , you need this trick to fix it ) .
Problem gone since 5.1.3 today . By the way , i saw that the numbers in noscript.net/?ver=5.1.3&prev=5.1.2 were the other way round , that is noscript.net/?ver=5.1.2&prev=5.1.3 or something alike , i´m not sure about ¨ver¨ ? !
This hour after finding 5.1.3 , every time i close down and restart Firefox ( or pc ) , i get a kind of homepage of noscript , wrong , it is the usual report after upgrade noscript.net/?ver=5.1.3&prev=5.1.2 , on my screen , again and again , plus icon and low bar . Very welcome , it seems that my trick has become standard . Anyhow , i don´t have to invite an update to get the icon back this hour .
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:56.0) Gecko/20100101 Firefox/56.0