Maybe this is a known issue since I've been away for a while, not sure...
 
I have an old song I'm working on and some of the tracks are frozen. The VSTs and VSTis the tracks use are long gone, so fortunately I have the frozen audio to know what they sounded like.
 
I cloned one of those tracks to see if I can unfreeze it and get the original MIDI clips without potentially losing the frozen audio. I know there are countless other ways to preserve the audio (or getting the original MIDI clips), like copying the frozen audio clip, making a backup of the project etc. But since I ran into this issue I'm just curious about the bug.
 
On the cloned track, the freeze button isn't blue so you can't unfreeze it. I played with the clone options but it didn't help. Is there another way to clone a track and keep it unfreezable?

Never tried or thought about this before, but it appears that cloning a frozen synth track just makes a new pointer to the audio file like cloning any other audio track. The state of being frozen is not cloned. But if all you want to do is preserve the audio, you can just unfreeze the original track, and the clone is your "backup" rather that the other way around.
 
If it's a Simple Instrument track, I recommend splitting it, and copying only the synth audio track. Cloning a SIT gets weird because it conflicts with the concept that an SI is one MIDI and one Audio track linked by a synth.