problem

Specific XLF files may contain multiple x tags in the same segment with identical IDs. This is unfortunately not breaking the specification.

The x tags with that non unique IDs were then considered erroneously by translate5 as tag pair (what they even are in the example when looking the semantic) but technically they are single tags - since a x tag - so they can not be marked as tag pair without breaking the tag check.

solution

Enable tag pairing on id base only for open and close tags, and disable for single tags like x, it and ph.