Twenty Fifteen theme jumping error

[kidsguide]

In the Twenty Fifteen theme, there is a wired jumping error when you scroll to the bottom of the page. Check out the video below.

​https://www.youtube.com/watch?v=3O73MC36Cc0

I am using the following:

• Windows 7
• A fresh install of WordPress 4.1 beta2
• Internet Explorer (the error does not happen on Firefox)

[kidsguide]

​https://www.youtube.com/watch?v=3O73MC36Cc0&feature=youtu.be

[ocean90]

Related: ticket:30366:26

[iamtakashi]

What version is the IE? I can't replicate it with IE11 in Windows 8.

[iamtakashi]

Correction: I managed to replicate the issue with IE11 on Windows 8 also. Investigating.

[kidsguide]

I am using IE11 in Windows 7.

[iamtakashi]

It's weird. For some reason, when the sidebar is longer than the main content, the height of document is 1px taller than the sidebar in IE... It should be the same height.

[kidsguide]

It is a very strange error. Hopefully we can figure it out.

[iamtakashi]

With a quick search, it looks like $( document ).height() doesn't always give you a cross browser, pixel accurate height. What about checking the body height instead? As far as I test, it works fine but I'd like to hear second opinions and needs more test.

[kidsguide]

Just tested your diff, and it works.

[cainm]

+1 on the diff

[iamtakashi]

Noting here that 30632.diff will also fix #30645.

[kidsguide]

Great!

[ocean90]

I can confirm that 30632.diff​ will fix this ticket and #30645.

30632.2.diff​ also replaces $( 'body' ) with $( document.body ) which is faster.

[iandstewart]

@cainm and @ocean90 thanks for the feedback.

[iandstewart]

In 30808:

Twenty Fifteen: correcting odd scrolling and jumping in IE and no-scroll with window resize.

Props iamtakashi, ocean90, fixes #30632, #30645.