I feel deadass collapse is unlikely but a civil war is quite likely, and in that case I hope NATO intervenes on the anti-Putin side.
I'd fight for the rebels, myself.
Most likely, you won't. I think that should a Russian civil war happen, there will be no side you'll like.
Do Russian liberals have war veterans? Do Russian liberals have supporters among military generals or special service operatives? Do Russian liberals have any significant hope for international volunteers?
To wage war, one needs someone who knows how to wage it. In 2014, Ukraine had very few people who knew how to wage war and we nearly collapsed against a very limited operation (and still lost a large chunk of territory)
But still, we had:
1) Afghanistan war veterans
2) Chechen war veterans (both Chehens who fled to Ukraine and Ukrainian volunteers that fought that war,
3) Badly funded and corrupt remains of the army of the Ukrainian SSR
4) Various paramilitary nationalist groups with some limited training
5) Some peacekeeping units that benefited from regular exercises with NATO
6) Civil resistance veterans of two revolutions who, while having no combat experience, had the necessary skills and organization to cover the logistics of the war.
What (and who) do Russian liberals have to wage a civil war? Why would any part of the Russian military machine join your side?