Lightroom will not open on my Mac

Lightroom (Lr icon) or Lightroom Classic (LrC icon)?

Please state the exact version NUMBER of your software. Please state the exact version NUMBER of your operating system. We need the version NUMBERs and not words like "latest" or "up-to-date".

Do you get an error message indication a crash? If so, what is the message? If not, please describe what you see and how far you get into the application opening process.

Some people report that LrC doesn’t launch, but then you say it crashes, these don’t seem to be the same thing to me. Can you clarify this?