Assegnate 5 su 5 stelle

Hi, I've been using Session Manager add on for many years in Seamonkey and I'm happy with it. But unfortunately it stopped working (it's shown in add on manager but doesn't display beside URL bar so cannot load/save sessions anymore) after I updated Seamonkey 2.53.16 to 2.53.17 and newer (the latest win x64 is 2.53.18.1). Would be possible to update the add-on to support this latest Seamonkey?