KKTeX submitted an update to the
modernruler
package.
Version number: 1.3.1 2026-01-26 License type: mit
Summary description: Flexible ruler and annotation commands with key-value support and vertical writing compatibility
Announcement text: ----------------------------------------------------------------------
Fixed a bug which occurs when \undernote command is used in mathmode.
From version 1.3.1 onwards, you can use \undernote command in math mode as follows:
[\undernote{x + y}{In the equation envriomnemt.} = \undernote{\frac{a}{b}}{No problem.}]
Some commands which are allowed to use only in math mode can be used in the argument of \undernote.
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This package is located at https://mirrors.ctan.org/macros/latex/contrib/modernruler
More information is at https://www.ctan.org/pkg/modernruler
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Thanks for the upload.
For the CTAN Team Erik Braun
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