What does カレンダー look like on Facebook?

On Facebook it is the design shipped in 16.0, shown above at full size. Older revisions are listed beneath it.

When did Facebook add カレンダー?

Facebook first drew カレンダー in 2.0, released 2017年2月20日.

Meta Platforms, Inc. has shipped 12 versions of カレンダー. Each is dated, so you can see when the design changed.

Facebook 4.0

This is the design Facebook introduced in 3.0, shipped again unchanged. It was not redrawn for this release.

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

What does カレンダー look like on Facebook?: On Facebook it is the design shipped in 16.0, shown above at full size. Older revisions are listed beneath it.
When did Facebook add カレンダー?: Facebook first drew カレンダー in 2.0, released 2017年2月20日.
How many times has Facebook redrawn カレンダー?: Meta Platforms, Inc. has shipped 12 versions of カレンダー. Each is dated, so you can see when the design changed.