For the Wikitext editor need an additional insertion of frequently used tags and templates. Using symbol insertion causes an error.
What we want to add can be seen in
https://ru.wikipedia.org/w/index.php?title=MediaWiki:Visualeditor-quick-access-characters.json&oldid=85782408
https://ru.wikipedia.org/w/index.php?title=MediaWiki:Visualeditor-quick-access-characters.json&action=history
https://ko.wikipedia.org/wiki/%EB%AF%B8%EB%94%94%EC%96%B4%EC%9C%84%ED%82%A4:Visualeditor-quick-access-characters.json
But the templates are opened immediately when you click on the insert symbol button. Console shows error
mediawiki.jqueryMsg: visualeditor-quick-access-characters.json: Parse error at position 0 in input: {