The launcher can run fine in offline mode, but when it comes to launching Minecraft It can't connect to the log-in server.
Linked issues
duplicates 1
Comments 2
Duplicate of MC-13810.
MCL-56
New Launcher has no Offline mode
Resolved
Duplicate
1
The old launcher had the option to play offline. The new one doesn't have the option to play offline, I really miss that feature.