Current behavior

When the tags are overflow, user unable to enter the new tag.

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Expected behavior

1. When the tags are overflow, its container should able to be scrolled.
2. User should able to enter new tag regardless number of tags existed.

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Steps to reproduce

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1. Keep entering new tag until it gets overflow.
2. Notice that no scroller even the tags are overflow. [X OK]
3. New tag is not allow anymore. [X OK]

Environment

• Version : master
• OS Version and name : UBuntu LTS 18.04.1 LTS

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