I had a ton of tabs that I have left on my phone which I was planning on viewing later. But I think after an update or some other reason, they've all dissapeared. They're not in the inactive tab group, they're completely gone.

Is there any way of getting them back? I feel as if they're still on my phone as using Firefox at that time did slow down my phone as a result and after they vanished it's still as slow with three tabs on there.