Hello!
I've been scavenging this forum for the past hours trying all different solutions. I did not update my arduino version and it stopped opening on my macbook pro. The icon appears and it says it is initializing packages but then crashes in a few seconds.
I have the 1.8.10 version installed -- already uninstalled and reinstalled it without success.
tried this link: https://forum.arduino.cc/index.php?topic=668724.0
but the response message is "The file /Users/mac/Arduino does not exist."
Had the same issue al afternoon and evening yesterday. I'm using OS 10.14.6 "Mohave" and after installing Arduino 1.8.13 hourly build everything is back to normal. Give it a try
I had the same issue as well -- installed and reinstalled 1.18.12, still no fix; updated macOS to 10.15.5 and repeated install/reinstall (also reinstalled Java). In the end switching to 1.18.13 nightly build offered a working solution until a longer-term stable option is available.