The LaTeX Team submitted an update to the
iftex
package.
Version number: 1.0c License type: lppl1.3c
Summary description: Am I running under pdfTeX, XeTeX or LuaTeX?
Announcement text: ----------------------------------------------------------------------
Update to iftex with no change to the user interface but internal tests now treat elax like undefined when testing for the existence of engine-specific commands.
So for example ifxetex is set to false if XeTeXrevision is undefined or if it is defined to be elax.
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This package is located at http://mirror.ctan.org/macros/latex/contrib/iftex
More information is at https://www.ctan.org/pkg/iftex
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Thanks for the upload.
For the CTAN Team Manfred Lotz
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