Re: Java plugin phase out timeline

I am using Firefox 53.0.2 32bit, how can I enable javascript add-on? I wish to digitally sign the e-tendering sites which are not opened anyway the message on the screen says- "Your connection is not secure. The owner of eprocuremes.gov.in has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website." 

Give me the solution.

Thanks
Suresh Acharya