If I had to pick only one artifact's worth: bash, probably. Otherwise:

• bash
• vim
• Linux (the kernel itself)
• Kubernetes
• Firefox
• urxvt
• Python
• pacman
• nix
• util-linux
• procps-ng
• iproute2
• iptables(-ng)/ebtables
• GNU parallel
• jq

The only chance we have that I see is the rapid development of fusion into a proper, usable power source, the supplantation of effectively all carbon emitting power plants with non-emitting plants (fusion or otherwise), the effectively complete electrification of the global commercial transport system, and a massive scaling of production direct carbon capture, leveraging the various aforementioned non-carbon emitting electricity sources to make it happen.

Technically, if you intend to return it eventually, it's not theft.

Theft, under the common law of England, as brought to the U.S., is the deprivation of personal property of another with the intention to permanently deprive them of it. If you don't have that intent, it's not theft. That's why we have "joyriding" and "grand theft auto" as separate things.

No. That's what the sane people wanted to do after the first vote came out as a demonstrably bad decision.

I like the smell of skunk.

What if they're espousing, either directly or by association, terrible things? Is that not the appropriate time?

I use my kids' step stool.

Bash defines zsh; not the other way around.