"He can have a lollipop any time he wants to. That's what it means to be a programmer."
The tutorial in wiki uses onClick event to change the picture, you did change that to onHover, yes?
"He can have a lollipop any time he wants to. That's what it means to be a programmer."
It will work if you have implemented it correctly. Many users have set it up with that tutorial. Do you have link to the site?
"He can have a lollipop any time he wants to. That's what it means to be a programmer."
The showPic js function is missing from your site source. Did you create the "mgJs" chunk and have &js=`mgJs` in the snippet call? Note that the chunk name is case sensitive. You can also put the js function straight to your site template if you want or an external js file.
"He can have a lollipop any time he wants to. That's what it means to be a programmer."