[out:xml][timeout:3600]; ( way(274579353)['wikipedia'='de:Nikolaus-Kopernikus-Gymnasium (Weißenhorn)']; ); (._;>;); out meta qt;//['wikipedia tag links to 404']
[out:xml][timeout:3600]; ( relation(7597737)['wikidata'='Q1886195']['wikipedia'='de:Maka']; ); (._;>;); out meta qt;//['wikipedia wikidata mismatch - wikipedia points to disambiguation page and wikidata does not']
[out:xml][timeout:3600]; ( way(1338577945)['name:etymology:wikidata'='Q71007; Q1098273']; way(4453191)['name:etymology:wikidata'='Q71007; Q1098273']; way(948252182)['name:etymology:wikidata'='Q71007; Q1098273']; ); (._;>;); out meta qt;//['malformed secondary wikidata tag - for name:etymology prefixed tags']
JOSM Wikipedia plugin
Note to self: online version hosted at https://matkoniecz.github.io/OSM-wikipedia-tag-validator-reports, files are stored at https://github.com/matkoniecz/OSM-wikipedia-tag-validator-reports.