Hi LuaTeX Team,
I am writing to report strange behavior of the \magstep0 command , or the original magnification \csname @m\endcsname.
The problem is happened in a macro with \afterassignment and then assign \magstep0 to a count register.
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The problem is happened in a macro with \afterassignment and then assign \magstep0 to a count register.
A shortest description:
```
\newcount\count
\def\problemhere#1\relax#2{\string#1#2}
\def\todo{
\afterassignment\problemhere
\count=
}
```
For the above macro, \todo\magstep1{HERE} just print HERE while \todo\magstep0{HERE} print \or1200HERE.
It seems that \magstep0 break the \ifcase structure in the \magstep definition, It seems that this is not a expected behavior.
Complete use case steps and more details are on the stackoverflow page

Sincerely,
Yours