When I Enter My Campaigns, Everything is Laggy

Everything seemed fine a day or so ago, but when I logged in last night, all the way up to now, everything is slow. Takes a bit for everything to load, there's a delay in all my actions, maps take a bit to load- everything's lagging. I do not know why this is happening. I am using Opera GX, but the campaigns were fine and I have been using it with no problem for the past months. Nothing on my end has changed and my games & connection outside Roll20 works very smoothly. So I am unsure what's going on.

I have the same problem though I am on Chrome. Every page takes a while to load, sheets open slowly. Sometimes when I roll off the sheet it goes through quickly, sometimes takes a moment to think. 

I have started experiencing the same Thing with Chrome. Noticed that chrome was using 6 GB of RAM. I switch ed over to Firefox and it only uses 1GB of RAM and everything is way smoother.  Try out Firefox and see if it feels better. 

There are  lot of anecdotal reports of better performance under Firefox recently. Browsers constantly evolve, and Roll20 is always adapting to these changes. Sometimes one browser's performance will leapfrog the other. Even though Firefox and Chrome are the only ones officially supported. my advice has always been "use whichever works best for you".