[combobox] Input and popup elements width mismatch when inheriting width with decimal places

[nkoene1]

Bug report

Current behavior

If the combobox field's width is dictated by the parent (e.g. a grid layout) and ends up with odd width values containing decimal places, the popup seems to have problems rendering its width the same way as the anchor field.

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Expected behavior

The width of anchor field and popup should be rendered the exact same as intended - even in the case of values with decimal places caused by e.g. percentage based width rules.

Reproducible example

StackBlitz Example

Base UI version

v1.1.0

Which browser are you using?

Behavior identical in Chrome and Firefox

Which OS are you using?

Mac OS

[linear]

BAS-381

[github-actions]

This fix will be available in the next npm release of Base UI.

In the meantime, you can try it out on our Canary release channel:

npm i https://pkg.pr.new/@base-ui/react@4082