Steps to reproduce

1. This issue happens when there are problems related to slow network (so you have to set your browser's development tools to Regular 3G or some similar setting) (I was able to reproduce it in Firefox + Network configured to Regular 3G)
2. Creating a page on https://demoauthor.magnolia-cms.com/.magnolia/admincentral
   • I attach my testpage-export
3. Edit the page and make some changes.
4. Save
5. Immediatly click the edit button on the second component (before the page is refreshed)
6. Edit the page and make changes.
7. Wait until the previous update has completely finished
8. Save

Expected results

Both components are updated independently.

Actual results

First component is overwritten with the wrong content, the second one is untouched. The content of the first component is lost!

Workaround

Wait until the page is completely reloaded.

Development notes

It is true that it is difficult to reproduce.

The problem is more evident when the changed components are using the same template, in this case the content is overwritten (because properties names are the same). If different, the "new" properties are added to the component content.