SeleniumHQ/selenium · error · NotImplementedError

You may only deselect all options of a multi-select

Error message

You may only deselect all options of a multi-select

What it means

`deselect_all()` clears every option, but only multi-selects support multiple selections. On a single-select it raises `NotImplementedError` because deselect-all is undefined for non-multiple selects (a single select always has exactly one chosen option).

Source

Thrown at py/selenium/webdriver/support/select.py:155

                    if not self._has_css_property_and_visible(candidate):
                        raise NoSuchElementException(f"Invisible option with text: {text}")
                    self._set_selected(candidate)
                    if not self.is_multiple:
                        return
                    matched = True

        if not matched:
            raise NoSuchElementException(f"Could not locate element with visible text: {text}")

    def deselect_all(self) -> None:
        """Clear all selected entries.

        This is only valid when the SELECT supports multiple selections.
        throws NotImplementedError If the SELECT does not support
        multiple selections
        """
        if not self.is_multiple:
            raise NotImplementedError("You may only deselect all options of a multi-select")
        for opt in self.options:
            self._unset_selected(opt)

    def deselect_by_value(self, value: str) -> None:
        """Deselect all options that have a value matching the argument.

        Example:
            When given "foo" this would deselect an option like:

                `<option value="foo">Bar</option>`

        Args:
            value: The value to match against

        Raises:
            NoSuchElementException: If there is no option with specified value in SELECT
        """
        if not self.is_multiple:

View on GitHub (pinned to aa36b38e69)

Solutions

1. Check `select.is_multiple` before calling: `if select.is_multiple: select.deselect_all()`
2. For a single-select, 'clear' by selecting a different/blank option instead
3. Catch NotImplementedError to handle single-selects gracefully

Example fix

// before
select.deselect_all()

// after
if select.is_multiple:
    select.deselect_all()
else:
    select.select_by_index(0)  # reset to default

if select.is_multiple:
    select.deselect_all()

def is_multi(select_obj) -> bool:
    return bool(select_obj.is_multiple)

When it happens

Trigger: Calling `select.deselect_all()` on a `<select>` without the `multiple` attribute (`is_multiple` is False). The guard `if not self.is_multiple:` fires immediately.

Common situations: Generic helper code that assumes all selects are multi-select; a select that lost its `multiple` attribute after a page change; test reuse across different form types.

Related errors

• You may only deselect options of a multi-select
• Could not locate element with value: {value}
• You may only deselect all options of a multi-select
• You may only deselect options of a multi-select
• Select only works on <select> elements, not on {webelement.t

AI-assisted analysis of SeleniumHQ/selenium@aa36b38e69 (2026-08-14). Data as JSON: /api/errors/00cd9cc46d25224d. Report an issue: GitHub.