The title says pretty much everything. I run into this situation when I've tryied to get the source code of one of my page (the controller was only accepting post request).
Is it the only browser doing this? Is there any advantages?
I've read some discussion about it. IMHO it should not be like that, since it could have many undesirable side effects.
Maybe you should ask directly to the Chrome folks?
I am not sure why it is explicitly a get request - that is probably something missed, but the reason it performs a refresh is because JS may have modified the DOM tree since the page was downloaded, so it makes sense to get the original. Although it could cache the original result before running any scripts instead...