Validate wikidata tag wrt. wikipedia tag

[simon04]

From ticket:10148#comment:description:

Show a validator warning if no Wikidata item is found (the Wikidata item may not exist yet; or the value entered may contain an error.

Show a validator warning if two or more Wikipedia articles are linked, with different Wikidata item IDs (may indicate an error; or there may be duplicates on Wikidata).

[floscher]

This is now implemented (see ​f443e9a) and will land in the next release of the plugin.

[floscher]

The following validator warnings are now released as part of ​release v1.0.1:

• error if wikidata=* contains something that currently does not exist as an item on ​https://wikidata.org
• warning if wikidata=* contains the Q-ID of a Wikidata item that is a redirect (this warning can be fixed by clicking the "Fix" button in the validator)
• warning if the wikidata item associated with the article from wikipedia=* does not match the item from wikidata=*

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Show a validator warning if two or more Wikipedia articles are linked, with different Wikidata item IDs (may indicate an error; or there may be duplicates on Wikidata).

That would not be an error, if anything the opposite case could be flagged (when the items are the sam). According to ​https://wiki.openstreetmap.org/wiki/Key:wikipedia#Secondary_languages wikipedia tags for secondary languages should only be present when the associated Wikidata item is different. The reasoning being that Interwiki-Links can and be resolved by data users.