the character '+' is not correctly rendered in wiki text inside monospace symbol

This

{{ i += 1}}

is rendered incorrectly. The '+' is interpreted as the underline meta symbol inside the monospace '{{}}' meta symbol. Meta symbols inside the monospace symbol should not be interpreted but outputed verbatim.

Also, escaping like this

{{ i \+= 1}}

does not work either - produces wrongly html encoded output.

screenshots :