Steps to Reproduce
Navigate to Collaboration> Live Feed.
Click the down arrow in the Search field and ensure that the selected Order Messages By setting is Created.
Post a new message, which should appear at the top.
Scroll down to an older message and comment on it.
Change the Order Messages By setting to Last Activity.
Click Search to apply the setting.
After the page reloads, note that the commented message is not shown at the top of the list where it should appear.
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Related Problem: PRB670737