Last modified: 2009-08-17 22:06:07 UTC
When an article is blanked and then immediately reverted, the article will drop out of whatever categories it is in (even though the category tags remain). The article will not find its way back into the category lists for several days or until another edit to the article has occurred. The issue can be viewed as of this writing on en:July 6. Page blanking was reverted two days ago.
Another example: en:April 24 was blanked four days ago and still does not show up in its cats. April 19 blanked two days ago.
*** This bug has been marked as a duplicate of bug 17154 ***