Is there any way to stop wildfires?

Sadly no, there's no way to stop any kind of fire, you're just supposed to let it die on its own.

You can act preventively, setting up your crops and your eventual reserve of wood with enough space to reduce the damages, but in the end, in case of fire, you can just sit back and collect charcoal and ashes afterwards.

Even rain, that by logic should help controlling the fire, actually makes the fire consume the objects more quickly.

Is there any way to stop wildfires?

It really depends on the layout of the forest and ignition point. In most cases, once a tree in a densely lit forest goes up, the rest will as well; your only option is to run for your life.

That said, if the fire starts out at the edges, in an area that is less dense, then it may be possible to run in and chop a tree or two down to create a firebreak, but timing is critical.

For example, I had a dense forest with some spider nests around. I wanted to set up a campfire so that I could hang around for a few days while carefully clearing out the nests, but there was nowhere safe to start a fire without igniting the whole forest. I went to the corner against the shore and chopped a couple of trees to make a gap and was able to make a campfire. I also backed up my save-game so that I could do some experiments like burning the spider nests without burning down the forest which I did successfully by burning a tree next to the nest after chopping down a few trees between those and the rest of the forest. Finally, during one experiment, it rained and lighting struck and started a fire near the edge. I was able to run ahead and chop down a tree to stop the spread. Of course this was possible due to a confluence of fortunate circumstances including:

• I already had an ax with low-wear equipped which saved valuable time
• The fire started at the edge, in a sort of “tail” or “galaxy arm” which was kind of like a fuse, so “cutting” it was effective
• (Somehow) I happened to have the presence of mind to compensate for the time it takes to chop down a tree and managed to run sufficiently ahead of the fire to be able to cut it down before the fire reached it

So yes, a forest fire can be stopped, but only under the right—and rare—circumstances.