Please Help about variable

Thanks for this very good plugin 🙂
I can’t seem to get the variable stuff to work though. Can you help?

I am admin and I would like my editors to be able to easily embed google maps of their choice. I then need to use a variable. The editor would then enter the html code (iframe) given to them by Google Mpas.

This is what I wrote in the settings for this snippet:
Title: google-map
Variables: iframe (“Shortcode” is ticked)
Snippet: {iframe}

When I try to use it on a page, I get the shortcode window with the field for the variable and on the backend,it seems to work. But on the frontend, it displays NOTHING.

Here is the line of code that is generated in text view:

[google-map iframe="<iframe style="border: 0;" src="https://www.google.com/maps/embed?pb=!1m14!1m8!1m3!1d2521.0806778792153!2d4.4045879999999995!3d50.8111439!3m2!1i1024!2i768!4f13.1!3m3!1m2!1s0x47c3db2ce9861ab3%3A0xf7692459ac5fb52b!2sRue+des+B%C3%A9gonias+55%2C+1170+Watermael-Boitsfort!5e0!3m2!1sfr!2sbe!4v1411590676042" width="300" height="300" frameborder="0"></iframe>"]

I must have set somehing wrong on the setting page. Can you help me?
If you need more info, please ask.
Thanks in advance.

https://ww.wp.xz.cn/plugins/post-snippets/