Some characters are not recognized non-CJK characters to skip

[tushuhei]

example
input: 今日は [@foo]tushuhei.com/hoge[/@foo]天気です。
output:

<span><span class="ww">今日は [@</span>foo]tushuhei.com/hoge[/@foo]<span class="ww">天気です。</span></span>

It seems characters like [, @ are included in a chunk by error.