Scenes disappearing from my Table

So I finished creating some of the scenes the other day, I managed to save the scenes before I leave, but then on the next day, the Scenes disappeared from my list, for it only displayed some of my scenes hadn't disappeared.

What's going on?
My browser version is: (do not change)
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:60.0) Gecko/20100101 Firefox/60.0

Did you clear cookies? If you cleared cookies or switched browsers, then it deletes your scenes. If not the data have been corrupted, but i'm not sure.

Scenes save in browser, this means they won't carry over if you change browsers or computers. They will also be deleted if you clear your internet history, browser cache or cookies.