akiko

Oh yes, typo, sorry.

https://files.minecraftforge.net/maven/net/minecraftforge/forge/index_1.14.3.html view all versions and download installer 27.02.21 or any below really works and the error doesn't occur. But versions in the laucher above 1.12 are still not visible for me.

I have the same exact problem. All the versions from 1.12 and below are visible but 1.13 and 1.14 not. I also had this error earlier but I resolved it with dowloading an older version of Forge- 27.0.20.