According to html5.org, the \"number\" input type\'s \"value attribute, if specified and not empty, must have a value that is a valid floating point number.\"
Yet it
I just had the same problem, and I could fix it by just putting a comma and not a period/full stop in the number because of French localization.
So it works with:
2 is OK
2,5 is OK
2.5 is KO (The number is considered "illegal" and you receive empty value).