Not possible to choose an option with empty value, because it used as placeholder

[Fedik]

Describe the bug
Since #617 is not possible to have an empty value in multi-select.

To Reproduce
Steps to reproduce the behavior.
Create a multiselect field with:

<select multiple>
  <option value="">All</option>
  <option value="1">1</option>
  <option value="2">2</option>
  <option value="3">3</option>
</select>

Expected behavior
You should be able to select "All", as it in native <select> behavior.

Additional context
Choices should not take an empty option as placeholder. If placeholder is invalid attribute (#447), then data-placeholder is pretty valid attribute

[ksouthworth]

I'm also dealing with this issue, does anyone have a solution or a workaround?

[Xon]

Implemented as part of #1166