On enwiki (but not on commons or simplewiki) the "help" icon when looking at page history has a misplace [ in front: [ (icon) help. This can be seen at, eg, https://en.wikipedia.org/w/index.php?title=User:DannyS712&action=history.
Description
Description
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Not here:
Which skin? Does this still happen in safemode (see https://www.mediawiki.org/wiki/Help:Locating_broken_scripts )?
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In vector, and safemode fixed it, as did commenting out my common.js, so its a script issue. Sorry