Compilation of our Seminar example file fails on updated TL20. The
maintainer of "Seminar" is not planning to fix the core issue and
states the following (in a private email with permission to quote):
it is a problem with the new hook management of the current latex.ltx
seminar is a quite old package and there is no reason to use it with a
new LaTeX format. It won't be fixed, so the usual way is to use the
package latexrealease to get the old hook management.
This commit adds a note to the example files explaining the
workaround of exporting to a .tex file and prepending the following
line:
\RequirePackage[2020-02-02]{latexrelease}
We now invert the relevant tests.