I know that you have to change something in the jvm arguments. However, I don't know what.
Your Java version is probably too new for the old Minecraft versions. Several Linux users have had the problem in the last few days.
You have to download old Java (Java 8) and tell Minecraft to use it.
Here are the instructions:
Open Bash / Terminal and type: sudo apt install openjdk-8-jre
Open the Minecraft Launcher
Click Installations
Double-click the 1.8.9 installation
Click on "More Options"
Change the Java program file to the path / usr / lib / jvm / java-8-openjdk-amd64 / bin / java
https://www.reddit.com/...happening/
Get in touch if you have any questions or what doesn't check in the instructions. (And also like to write if it worked).
Thank you! Do you know why it loads so long when I go to gtt in ttt or something?
Nope, no plan. Isn't it because of the ping?
Nope
Maybe there are a lot of player heads, banners, entities or something similar. Always used as a decoration. Then it always takes a few seconds for the world to load. Haven't played TTT in a while, so I don't know. Maybe your PC is simply no longer the newest. I don't know any other reason now without looking up myself.
Yes, it is no longer the latest, but it is the same with other modes. And at 1.15 the loading time was not that long
