Steps to reproduce the issue

forked from #34284

If you manipulate the HTML option value in a select list which has in its field definition validate="options", and set the value="" when no "" value existed in the options previously, the validation will still PASS when the form is submitted! This is not correct, because this is a manipulated value, and "" did not exist in the options to choose from.

Expected result

If you have a field, which has validate="options" in its XML definition. Renders something like:

<select>
  <option value="this">THIS</option>
  <option value="that">THAT</option>
</select>

and you change that to be <option value="">THAT</option> by manipulating the HMTL of the page and then click save, the validation should FAIL because "" is not this or that

Actual result

Passes validation

System information (as much as possible)

Additional comments