Sparanoid

Corner Bracket Lover converts all curly quotation marks (“” and ‘’) in your posts to traditional corner brackets (「」 and 『』). A must-have plugin if you’re a Chinese writer or just a corner brackets lover. This plugin also works fine with multisite enabled WordPress (aka. WordPress Mu).
More information please visit my <a href="https://sparanoid.com/work/corner-bracket-lover/" rel="nofollow ugc">site</a>.

Corner Bracket Lover

Corner Bracket Lover converts all curly quotation marks (“” and ‘’) in your posts to traditional corner brackets (「」 and 『』).

edik

Some WordPress functions outputs character entity references. The most of these are not allowed in XHTML. So if your WordPress installation uses the mime type ‘application/xhtml+xml’, the generated sites could have invalid xhtml code and the browser would display the syntax error page.
Convertentity converts all entity references into their corresponding characters with the exception of the references for the following characters: ‘<>&”
Theses references are the only ones which are allowed in XHTML.

Convertentity

Converts all character entity references, which are forbidden in XHTML, into their corresponding characters.

Corner Bracket Lover vs Convertentity