Ton Van Hest wrote:
How to get rid of this new version and back to the old. Without having to reinstall everything?
The previous Safari version could be restored from the Time Machine but the new version needs to be forcibly removed first, the OS will not allow a simple move to Trash.
The command below will remove the unwanted version but take care, there is no undo to this operation. (To avoid mistakes the Finder in List view with the 'Version' column enabled is good.
sudo rm -rf /Applications/Safari.app
Extensions will need to be re-enabled.
The other option is to wait for Apple to undo the mistake.
I have got rid of the Seed here.