this looks very similar #3024
can you please check whether it fix the problem?

#3024, seems to try to deal of the same problem,
but only inside validateField

My suggested fix is at a more proper place making sure that no member functions are called on non-object

I am sorry i did not connect pull request with e.g. this issue: #5411

This pull request fixes this:

In IE8 and IE9
form.elements also contains function names
(code is supposed to take care of this ?? but it does not)

After calling (exists in 2 places inside the file)
var self = elem.form.H5Form;

We need to test if "self" is an object aka a form element, and do this:
if (typeof self != 'object') return true;

The return true is needed so that function
validateField(...)
will work properly

if (typeof self != 'object') return true; it not really safe as null also object,
I would suggest just if(!elem.form || !elem.form.H5Form) return; .. as in another issue

@Fedik

Basically the problem is that: elem.form.H5Form
is 'undefined'

so your code will work too, but also checks if elem.form is 'undefined' (which i don't know if it is possible with existing code)

just we need: return true;
and not just: return;
so that validateField(...) will work

yes !elem.form.H5Form will check whether property is not: null, false, undefined or 0.
About return true you are right, of course

I have updated the PR according to Fedik suggestion

please update also html5fallback.js
as html5fallback-uncompressed.js only for debug mode

Added

@ggppdk - I'm more than happy to test this as I have IE8 at work for testing purposes, however could you please explain the test process, so I know what to add and where?

Cheer,
Lodder

@ggppdk please provide some testing instructions as requested. I'm afraid that without testing instructions people just dont test things and it will sit here for another year. If instructions are not provided this will be closed in 4 weeks time.

Closed as stated above