False positive: "an Xcode" is flagged to change to "a Xcode"

Perhaps being titlecase would be a hint it's pronounced more like in x-ray than in xylophone?

No file, test, or entry point is identified. Start by reproducing the reported false positive for “an Xcode,” then locate the grammar rule responsible and add regression coverage; done means the valid wording is no longer flagged while comparable article errors remain detected.

Written by the indexing model from the issue text.