What does 1曲リピートボタン look like on HTC?

On HTC it is the design shipped in Sense 8, shown above at full size. Older revisions are listed beneath it.

When did HTC add 1曲リピートボタン?

HTC first drew 1曲リピートボタン in Sense 7, released 2015年3月30日.

HTC Corporation has shipped 2 versions of 1曲リピートボタン. Each is dated, so you can see when the design changed.

HTC Sense 7

HTC shipped a new design for 1曲リピートボタン in Sense 7, released 2015年3月30日. The previous design is shown beside it.

The first HTC release we hold for this emoji.

✳ marks a release that redrew this emoji. The rest re-shipped the design unchanged.

What does 1曲リピートボタン look like on HTC?: On HTC it is the design shipped in Sense 8, shown above at full size. Older revisions are listed beneath it.
When did HTC add 1曲リピートボタン?: HTC first drew 1曲リピートボタン in Sense 7, released 2015年3月30日.
How many times has HTC redrawn 1曲リピートボタン?: HTC Corporation has shipped 2 versions of 1曲リピートボタン. Each is dated, so you can see when the design changed.