Footer theme content does not display as expected in staged environment.

When staging is enabled and the theme applied has the capability to display footer web content, there is an issue. Take for example the new Zoe themes which have theme settings where you can put in web content ID's to display content.

Steps to reproduce:

1. Install/choose a theme that has settings for footer content (Zoe themes, for example).
2. Enable staging for the site
3. Create web content (note the web content ID for next step)
4. Paste web content ID in theme's settings for one of the footer content locations
5. Observe that the content is displayed in the footer as expected in the staging environment.
6. Mark for publication
7. Publish to live
8. Observe that the footer content is not displayed at all.

I realized that this is caused by the differing content ID's in staging/live. As a workaround, I took the following steps:

1. Place a web content portlet on the page
2. Select the web content I would have placed in the footer
3. Mark for publication
4. Publish to live
5. View source and observe the web content div's id (something like id="article_17037_17062_32860_1.0")
6. Write down the last 5 numbers of the id (32860)
7. Go back to staging environment
8. Remove web content display
9. Place the id number obtained previously in the theme settings for footer content
10. Observe that the footer content is NOT displayed because we are still in staging.
11. Mark for publication
12. Publish to live
13. Observe that the web content IS displayed because we used the live web content id rather than the staging id.

This should help to illustrate the problem. As you can see, this is not really a viable work around because it's so involved.