firefox so very slow

this new version is horrible. I go to Facebook and it either does not come up or it takes forever. It does it with addons on and off and i do not get half of what i post and there are just colored square no post all when i go to my page but yet it works just fine in Chrome with both extension on and off. I have cleared the cache history etc and still nothing have removed some add ons added some adblockers and it will not let me me see my notifications for at least 5 minutes and that is about how long it takes for it to work on fiirefox with and with out extensions it is a little better with out add ons If this happens with add on you recommend then why do i need them why have and offer theme them if it causes this. have tried contacting Met AI and Facebook but it only happens with Firefox why do this if it aint broke do not fix it