Same here. Coincidentally I just upgraded from 8 GB to 32 GB and this was the first time my new RAM was full. FF ate 30 GB! :-)

I also didn't saw the memory usage in process manager, only in Windows Task Manager. Also interesting: Closing the tab did not release the memory, the process keeps eating more RAM until I kill it. By the way, I'm using FF 115.14.0esr.

Where do you monitor this? In the Firefox process manager, I see that it eats ~120 MB.