Unexpected token ILLEGAL

My code:

var foo = `bar`;

If I paste it on the left side of the IDE (Web IDE version 0.70.6) it works fine, if I try to upload it from the edit panel it gives the error message "Error: Line 1: Unexpected token ILLEGAL".

I'm using more complex strings also containing both single and double quotes, e.g.

var foo = `console.log('This is "cool".');`; 
var bar =`Line1
Line2`;
//storage.write, storage.read
eval(foo); 
console.log(bar);

A workaround would be var foo = 'console.log("This is \\\"cool\\\".");'; and
bar="Line1\nLine2", but that's hard to write. What's the cause of this error?