Terraria + tModLoader v0.11.1 install on macOS 10.14.5

# Step 1: Ensure the Terraria is removed

## backup and remove any previous Terraria data folders
## uninstalling from Steam does not remove these folders
## use `/Library` instead of `~/Library` if your install is global
rm -rf ~/Library/Application\ Support/Terraria
rm -rf ~/Library/Saved\ Application\ State/org.Terraria.savedState
rm -rf ~/Library/Application\ Support/Steam/steamapps/common/Terraria

# Step 2: Install Terraria from Steam

# Step 3: Test that vanilla Terraria runs:

~/Library/Application\ Support/Steam/steamapps/common/Terraria/Terraria.app/Contents/MacOS/Terraria

# Step 4: Install the Java JDK if you don't have it

## https://www.oracle.com/technetwork/java/javase/downloads/jdk12-downloads-5295953.html

# Step 5: Install tModLoader using the Jar

## the manual install (copying/pasting files) does not work
## there are missing files (*.dylib) in the `osx` directory

## change to proper directory
cd ~/Downloads/tModLoader.Mac.v0.11.1/

## execute jar
java -jar ./tModLoaderInstaller.jar

# Step 6: Adjust permissions of the executable
sudo chmod 755 ~/Library/Application\ Support/Steam/steamapps/common/Terraria/Terraria.app/Contents/MacOS/Terraria

## at this point, you should be able to run Terraria via CLI or Steam:
~/Library/Application\ Support/Steam/steamapps/common/Terraria/Terraria.app/Contents/MacOS/Terraria

# (Optional) Step 7:

## if you are still getting crashes, check the crash log:

more ~/Library/Application\ Support/Steam/steamapps/common/Terraria/Terraria.app/Contents/MacOS/client-crashlog.txt

## there may be permissions issues for other files, such as logs:

sudo chmod 755 ~/Library/Application\ Support/Terraria/ModLoader/Logs/client.log