Oh and in the meantime, if you want to keep playing I would recommend launching the game from the official itch.io launcher: https://itch.io/app. This bug seems to only occur if you download the standalone version.
If you are still not able to progress after opening it from the itch.io launcher, you may need to delete your save file located in: Users/<your name>/Library/Application Support/Finite Reflection Studios/Containment