How much can be saved?

At this point I believe that's the only real question to be answered. Not "can we stop global warming?". Not "is it reversible?" Not even, "what mitigations are achievable?"

Just a simple acceptance of the reality and taking a hard look at what might remain once the changes really get going. How we might preserve a little more of the life and ecosystems that currently exist, than might otherwise survive.

How much knowledge, in what form, may be of most use to those that come after?

That's all. If you haven't reached this point in your thinking yet, that's ok, keep going.

When you're ready to do what is required, you won't be alone. Don't wait too long before reaching out, and finding each other though. The necessary work is simply not possible for one or even a few.

Wake up folks. Find your people. Do the work and prepare yourselves.

Remember, this has never happened before. You're going to have to be resilient, smart, adaptive, and most of all fit and strong.