It seems to be impossible to leave the select open for testing style in Developer Tools. After selecting an option from the dropdown, the dropdown vanishes, so testing styles is impossible.
Is it possible by adding a class to the select, or similar method?
Using vue-devtools, send the component to your console, then go $vm0.open = true.
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Using vue-devtools, send the component to your console, then go
$vm0.open = true.