Most promising approaches as of 2020:

Why Private Billions Are Flowing Into Fusion by Bloomberg (2022)

Joint European Torus
General Fusion: compress with liquid metal. Intends to demo in JET site.
Helion Energy: direct fusion to electricity conversion without steam, direct from magnetic field movements
First Light: shoot microscopic objct at a target to crush it so much that fusion happens

It is interesting that there are several different approaches to the problem. This feels a bit like quantum computing's development at the same time, increases hope that at least one will work.

Magnetic confinement fusion

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Once again, relies on superconductivity to reach insane magnetic fields. Superconductivity is just so important.

Ciro Santilli saw a good presentation about it once circa 2020, it seems that the main difficulty of the time was turbulence messing things up. They have some nice simulations with cross section pictures e.g. at: www.eurekalert.org/news-releases/937941.