At least the “medieval warm period” which gets cited a lot, was a regional phenomenon and global temperatures are higher today. At least the Wikipedia page seems to suggest the same for the Roman warm period.

I’ve read that most visible flames in campfires are just glowing soot

I had the same problem and after I closed all other lemmy-tabs in my browser it worked.

but the UI is so ugly :(

Just want to add, that rust is not pure iron oxide(? can’t do chemistry in english) but also contains water molecules