Viewport addon has unnecessary scrollbar when dimension is set to 100%

[mtlewis]

When one of the dimensions of the viewport is set to 100%, the additional margin added around the iframe causes an unnecessary scrollbar. Since the height is a percentage, it doesn't seem to make sense to force the content to be exactly 100% of the height of the storybook preview area - instead, it should probably take the extra margin into account.

To Reproduce
Steps to reproduce the behavior:

1. Configure the viewport addon with a viewport with either width or height set to 100%
2. Choose that viewport
3. Observe that the viewport is slightly bigger than the available space.

Expected behavior
Viewport size is reduced slightly to avoid the unnecessary scrollbar. Note that this should probably do the right thing even if the viewport is close to 100%.

Screenshots
Current Behaviour:

Proposed Behaviour

[stale]

Hi everyone! Seems like there hasn't been much going on in this issue lately. If there are still questions, comments, or bugs, please feel free to continue the discussion. Unfortunately, we don't have time to get to every issue. We are always open to contributions so please send us a pull request if you would like to help. Inactive issues will be closed after 30 days. Thanks!

[stale]

Hey there, it's me again! I am going close this issue to help our maintainers focus on the current development roadmap instead. If the issue mentioned is still a concern, please open a new ticket and mention this old one. Cheers and thanks for using Storybook!