Ever since Minecraft 1.9 was released, I've been facing this problem every time I try to start the game. For example if I select the most recent version, 1.11, it will download all the assets like with all the other versions, and the launcher disappears like the game is about to start. Then the launcher appears again and a bunch of text that appears in the Game Output tab that says

"Can't find or load main class net.minecraft.client.main. Main
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release"

Screenshot of the issue (First sentence is in Swedish): https://gyazo.com/bfdf4a5f17e27a32bf19855373baf094

I've tried to reinstall Minecraft and Java a couple of times to ensure that I have the latest and the most fresh version of everything, but this problem is still appearing whenever I try to play the game with the original launcher. Using a 3:rd party launcher like MultiMC or other works, but it makes things more complicated that using the original one.