Category:Pages using xtag template with unsupported tag name

It is used to build and maintain a list or lists of pages—primarily for the sake of the lists themselves and their use in resources and category maintenance. It is not part of the categorization scheme for learners.

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This category is hidden on its member pages—unless the corresponding user preference (Appearance → Show hidden categories) is set.
These categories are used to track, build and organize lists of pages needing "attention en masse" (for example, pages using deprecated syntax), or that may need to be edited at someone's earliest convenience.
These categories also serve to aggregate members of several lists or subcategories into a larger, more efficient list (discriminated by classifications).
Typically, tracking categories are automatically populated by templates invoked in pages or by the MediaWiki software (see Special:TrackingCategories for an overview of the latter).

Custodians/Curators: Please keep this category, even when empty!
This category may be empty occasionally or even most of the time.

Pages in category "Pages using xtag template with unsupported tag name"

This category contains only the following page.

X

Template:Xtag