How to get this work with codemirror?

As iframe-URL
http://visualmatheditor.equatheque.net/VisualMathEditor.html?codeType=Latex&encloseAllFormula=false&equation=a%3D1
it works.

I tried to quote the complex-equation parameter with urlencode, that was not the problem
http://visualmatheditor.equatheque.net/VisualMathEditor.html?codeType=Latex&encloseAllFormula=false&equation=%5Cvec%7BF%7D%2520%3D%2520%5Cfrac%7Bd%2520%5Cvec%7Bp%7D%7D%7Bdt%7D%2520%3D%2520m%2520%5Cfrac%7Bd%2520%5Cvec%7Bv%7D%7D%7Bdt%7D%2520%3D%2520m%2520%5Cvec%7Ba%7D

Problem is in my installation that the input field for the URL only accepts 128 bytes (maxlength). in iframe.install the URL field have a length of 1024.

(if url save directly to db (there is place for the 1024 bytes), then the iframe-module can show the virtual editor with whole equation)
http://www.neffets.de/node/33

I have to fix the 128-maxlength problem

BUG fixed. Added the missing "maxlength" attribute to form definition. Fixed in release 7.x-1.2

Attribution goes to Issue #2300159 by ohthehugemanatee too, because he has found the solution earlier.