A new ceiling for Λ: the de Bruijn–Newman constant is at most 0.1787854

What happened
A walkthrough of Jude Gomila's computer-assisted proof lowering the ceiling on Λ from 0.2 to 0.1787854.
Summary assembled by rule from the sources below

A walkthrough of Jude Gomila's computer-assisted proof lowering the ceiling on Λ from 0.2 to 0.1787854.
Summary assembled by rule from the sources below