Heat Diffusion Demo

I saw that there isn’t a heat diffusion demo, would it be helpful to work on creating that? Looking to take this as my start to contributing.

There is a heat equation demo at: The heat equation — FEniCSx tutorial

For contributions, I would check out: GitHub · Where software is built
or ask in the #development channel on slack if someone has anything else in mind as a new good first issue to handle.

Can I please get an invite link for slack, the one of github is expired.