The undo class
Three classes of reversibility, the ordering on every rendering this site produces, and the one column that is not fully context free.
Source: https://abp.sgit.ai/model/undo/index.html↗ · site v0.11.0 · this file is generated from the same content
as the page, so the two cannot drift. Every page on this site has a .md twin; internal links
below point at them.