Comments/worknotes do not clear in the journal entry textarea after they're posted on workspace

Comments/worknotes do not clear in the journal entry textarea after they're posted on workspace

1)Open an existing record or create a new record of incident/case
2)Change a field on the form like assignment group/assigned to / priority
3)Now, add a multiline text on worknotes and click on post

Expected behaviour:comments should be posted and field should not show values that are typed.

Actual behaviour:comments are posted and field is showing the same values that are typed.

Apologies for the inconvenience. Our dev team has skipped below versions and the targeted the fix for Vancouver release. 

    Tokyo Patch 9

    Utah Patch 4 versions.

Please upgrade your instance to Vancouver to fix the issue.