minor #16436 [Form] Add inputmode doc for NumberType (welcoMattic)

This PR was merged into the 6.1 branch.

Discussion
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[Form] Add inputmode doc for NumberType

Ref #16433

The code is already merged in symfony/symfony#45101

Commits
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f913d04 Add inputmode doc for NumberType

Author: javiereguiluz

reference/forms/types/number.rst

@@ -58,6 +58,13 @@ to ``2``, a submitted value of ``20.123`` will be rounded to, for example,
 
 .. include:: /reference/forms/types/options/rounding_mode.rst.inc
 
+If set to ``0`` with ``html5`` set to ``false``, the HTML input will be rendered with ``inputmode=numeric``.
+However, if set to any value greater than ``0``, with ``html5`` set to ``false``, the HTML input will be rendered with ``inputmode=decimal``.
+
+Learn more about the ``inputmode`` attribute on `MDN website`_.
+
+.. include:: https://developer.mozilla.org/fr/docs/Web/HTML/Global_attributes/inputmode
+
 Overridden Options
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