Hi, my adobe flash has stopped working on websites if i use firefox. the timer shakes and flash does not load

The timer shakes and flash does not load I have followed most of the instructions already posted. plug ins says I have the plug in, and it is on 'always allow' Lexulous..a scrabble site, lets me go to the website, but I can't get the game component to download. Chrome does it fine.want to show live on CCL 2017 I tried some other sites and it seems to be Flash. it was working fine until 3 days ago.