Since while I cannot set the value of an input field with type=text. Before, I always used something like this:
<input style="display: none" type="text" name="geo_poi" value="" id="geofeld" />
Then, in JavaScript i added code containing a line like this:
document.getElementById("geofeld").value = geo_poi;
This always worked. Maybe the new browsers don't want to support the method above anymore.
So using the following method for setting attributes worked fine.
HTML
JAVASCRIPT
Jsfiddle HERE
For situations when setAttribute does not yield any result (think HTML5 user/password input), consider this: